House builders give their clients allowances for certain items, carpets for example, and the clients, with that allowance in mind, pick their favorite styles and colors. Plumbing fixtures are an exception.

"Builders usually don't give a plumbing allowance," says Tracy Bartlett, showroom manager at Westburne Supply Inc. "Instead, it's a set package of basic fixtures, and if the homeowner wants to make changes, he must pay the price difference."

Start early if you want to participate in plumbing-fixture picking. "Sometimes the fixtures are being installed before the homeowners know what's happening." Bathtubs, showers and faucets go in before sheet rock goes up, and special orders (which include colors except white or ivory) can take three or four weeks. Fixture shoppers should bring a copy of their floor plan to the store so the salesperson will know what size tubs and showers are specified.