1. My qualifications? My good taste, naturally.

Remember the days when you could very well expect to find a real treasure, say, a $20 Eames chair, at a garage sale? That was before the home-improvement craze of the past decade. Now everybody and his mother fancies themselves an interior designer sometimes literally and there are scant regulations defining what constitutes an interior designer or decorator. Only a little more than half of the states have rules establishing the qualifications a person must complete before legally calling himself or herself a licensed, registered or certified interior designer.

Of course, you may not care about such credentials if all you want is to hire the same person who made your neighbor s living room look fabulous. Advanced training, however, covers materials, safety, and code issues that can have a major impact on your home. Hiring someone who doesn t have that knowledge can result in a slip-and-fall from the wrong flooring or allowing the homeowner to go ahead with a design that can't be executed because of technical issues in the home, says Bruce Goff, a Reno, Nev.-based interior designer with the firm Domus. And now that we are seeing so many home-based businesses, it's a major issue for the electrical and ergonomic needs of a work space, he says.

So, do your homework. First, see what your state requires by checking out the International Interior Design Association s (IIDA) web site. Then visit the American Society of Interior Designers (ASID) referral site for a list of qualified designers in your area.

2. I ll decorate in my style, not yours.

Look over your designer s portfolio carefully before you make a hiring decision. If what you really want is a laid back and informal style, don t hire the designer who you met at a luxury show house. If you want a home done in whites, don t hire a designer who features color all over their web site, says Deborah Wiener, of the Silver Spring, Md., firm Designing Solutions.

It s important to match your style and lifestyle with what the designer is known for. Specializing in one thing means they don t know how to do anything else, says Beth Whitlinger, an interior designer in Rancho Santa Margarita, Calif. And you ll have better luck with a designer with whom you have a good rapport one reason to set up an early face-to-face meeting to compare opinions on, say, pictures of rooms you ve clipped from magazines.

3. I ll redesign your budget along with your rooms.

Unless you re careful, an interior designer may treat your budget like a swatch of discarded fabric. Designers assume that budgets don t include things like their fees and taxes, Whitlinger says, adding that they likely regard that number as the amount they can spend on furnishings and finishes alone. That s why you should explicitly tell your designer that the amount you re willing to spend includes everything: furniture, fees, sales tax, delivery, installation the works. Have the designer give you a proposal with everything itemized before anything is started, Whitlinger says. That way, you get a breakdown of how every penny is going to be spent.

A photo or drawing of the item should accompany the price proposal along with any finishes or fabrics that might be applied to the item. This way there are no surprises when the client receives their merchandise, Whitlinger says.

Wiener recommends putting together a range from low to high of what you want you want to spend, and be very direct during the interview and shopping process about what you re comfortable spending.

4. You have no idea how much that sofa really costs.

When you pick out new furniture with a designer, chances are that she will order it from a trade showroom at a discounted price in between wholesale and retail then add the markup for her time and service. But you might not know how much you re being charged, since bills often reflect just one lump price.

Most designers charge markups of around 30% or 40% for the items they purchase, says Marie Chan, an interior designer and principal of InterSpace Design in Santa Clara, Calif. Whatever you end up paying a designer for an area rug or curtains, it shouldn t be more than how much you could have gotten it at the retail price. I generally tell clients: This is the list price; I get a discount; how much depends on who I get it from. But after my markup, it will still be 20% to 30% below the retail price', Chan says.

Ask your designer about their fees and what the net cost of their purchases will be. I guarantee my clients they ll never pay more than retail for anything, says Anne Vincent, president-elect of the ASID Georgia chapter. Many designers are reluctant to divulge their net prices, but I have always thought the openness was best for client-designer relations, she says.

5. My hourly rate will make you see red.

Whoever you hire for a project, ask about their fee structure. Some charge a flat fee plus a commission based on a percentage of the cost of products, while others charge an hourly rate of $75 to $250 or more plus commission. Depending on how long your project will take, an hourly rate may be out of your budget especially when you factor in the possibility of being charged for office assistants placing orders and sending mail.

It s fine to work on an hourly rate, but it increases a client s comfort level if there s some sort of target an hourly rate against a guaranteed maximum, says Vincent. A better option might be to ask for a fixed fee. To calculate a fair price, consider that a simple room typically takes about 20 hours of designer work to complete.

6. Shop at the right stores and you ll pay less for designers.

Just because you don t want to spend upwards of $50,000 on your living room doesn t mean you can t hire an interior designer. National retail chains such as Bloomingdale s and Ethan Allen, along with some independent furniture stores, offer the services of trained designers at excellent rates. At Ethan Allen, for example, design service is free with a purchase whether you spend $100 or $10,000. Bloomingdale s fees depend on the location: The design store in Manhattan has a $2,500 design fee with a minimum purchase of $25,000, while the Chesnut Hill, Mass., store and King of Prussia (in Pennsylvania) store have a $750 design fee with a minimum purchase of $10,000.

The designer will also help order non-store products such as tile and curtains. Before you sign on, make sure your in-store designer is a member of a trade organization such as ASID or IIDA to ensure that you re working with a trained pro and not simply a glorified salesperson. Just like any hire, ask the designer for referrals, and get fee and purchase requirements in writing.

7. Using my contractors will cost you.

When it s time to lay new tile or paint your kitchen, your designer will likely recommend his preferred contractors folks whom he trusts to do the job. But taking these referrals can often be more costly than finding a contractor yourself thanks to the hidden referral fees, or kickbacks, that designers often get from their preferred contractors. For instance, if a painter normally charges $500 for a job, he may charge you $550 when it comes through a designer, then pass that extra $50 back to the designer.

Hidden referral fees are actually against ASID s ethics code, so ask your designer upfront about his policy. I would say it s rare. It s not a standard business practice, says Vincent.

But don t be automatically suspicious if your designer wants to hire people he or she has worked with in the past. Jerry Jacobs, an interior designer in San Francisco, says he likes to use his own contractors on clients projects for several reasons: He knows they re reliable, it saves time, and they know how he works.

8. Don t rush me or I ll have to charge you.

If it's October and you want your dining room redecorated in time for the holidays, designers have two words for you: good luck. Not surprisingly, the pre-holiday season is a busy time for the industry but so is spring, as clients anticipate summer visitors. That means interior designers don t have as much time for your project, and compounding the problem, furniture delivery anytime tends to be quite slow.

If a designer can do your job at what he considers a quicker than normal pace, it won t come cheap, says Jacobs. Rush fees, FedEx packages are passed on to a client as is the cost for a designer to wait in your home for a delivery.

9. Custom orders mean you re courting disaster.

Thanks to economics and industry consolidation, there s less standard stock furniture on showroom floors these days. As a result, custom furniture is becoming more prevalent, whether it means choosing different upholstery than what s on the showroom model or asking that the sofa be 96 inches long instead of 98.

Either way, custom orders can create trouble. If your custom-size sofa won t fit in your study or if a specialty-ordered chocolate chenille looks more like latte, tough luck once the product has passed the manufacturer s inspections, it s unlikely you can return it. To avoid such problems with custom orders, interior designer Bruce Goff says he makes his clients sign off on every step of the process, from the initial sketch to samples of the finish, fabric,or yarn, which are called strike-offs. For rugs, he recommends that clients buy a sample corner. At about $250, Goff says, It s the cheapest insurance you can get.

10. If I botch your project, good luck getting reparations.

You ordered the cherry bronze hardwood floors, and cherry fireside gets delivered instead. Did your designer order the wrong finish or did you get them mixed up? Like with any other service rendered, there will invariably be disagreements. That s why it s smart to insist that your designer prepare a letter of agreement or contract before any money changes hands, says Doug Stead, the executive director of the California Council for Interior Design Certification, the state s certification board for interior designers.

If there is a dispute over whether certain work has been performed, you may not always get your money back, but at least a contract should help clarify what recourse both the consumer and designer have. Make sure there s a dispute resolution clause in your contract, which spells out what happens if there s a dispute between the designer and client. This clause may mandate that the designer or client use an arbitration or mediation company, says Stead. It also spells out which party is responsible for which costs in the event that the contract is broken.

You should also make sure the designer has business liability insurance. That way, if you ve paid a portion of the cost of, say, a pricey Oriental rug they purchased for you, and the manufacturer s warehouse burns down, your designer is covered. Without it, you ve lost the money you paid them, says Stead.