Nancy Reagan has come to town with a wardrobe of clothes and accessories worth at least $25,000 to wear for the inaugural period. That tally comes from estimates given by designers and stores familiar with Mrs. Reagan's purchases and it includes the hand-beaded inaugural ball gown and coat designed by James Galanos and a Maximilian mink coat, a Christmas gift from her husband. The Maximillian replaces the black mink she has owned for 25 years, which designer Adolfo has recycled into a lining for her raincoat.

The tally of private purchases and gifts does not include the spangled dress she wore last night to the Kennedy Center, her outfits for today's events other than the gala, her jewelry and some of the shoes and underwear or the cost of her hairdresser. It does include a $1,650 American alligator handbag by Judith Leiber.

Nancy Reagan has many designer clothes, which she wears over and over again, and the wardrobe for the inaugural no doubt will be used the same way. Below is a shopping list for her inaugural attire with approximate prices.

A top-quality, full-length mink coat by Maximilian, the exclusive New York furrier whose mink coats usually start at $8,000 and generally go up to $12,000 for the best. Anna Maximilian Potok, who fitted Nancy Reagan, would not reveal the exact price of the coat. She did say that the midcalf length was suitable to be worn over daytime clothes as well as full-length gowns. "I'm sure Mrs. Reagan will wear it for different kinds of occasions," said Potok.

A hand-beaded inaugural night ball gown by James Galanos, America's most inventive designer, took several women four weeks to embroider. His gowns are motsly sold from sketches and swatches picked from a sample book and then made to order by hand in his Los Angeles workroom. A gold embroidered gown on the rack at Neiman-Marcus last year had a price tag of $10,000. Last fall, a plain gown and jacket costume with embroidery just on the jacket, could be ordered from his sketches of $5,000. Galanos "donated his services" for the inaugural dress, as he did the dresses she wore to the two California inaugural balls.And like the others, which were contributed to the Los Angeles County Museum, this one will join other First Lady gowns in the Smithsonian's Museum of American History.

Nancy Reagan will be wearing a matching Adolfo dress and coat inauguration day. She has long worn Adolfo suits, which start at $800. His dresses start at $600; his coats rarely are priced under $900.

Bill Blass evening gowns start at $1,200.When they have fur trim -- and Mrs. Reagan's dress for the gala at the Capital Centre has a fox-trimmed shrug -- the price zooms up to more than $2,500. (Barbara Bush also is planning to wear a Bill Blass hammered satin gown for the inaugural ball.)

David Evins makes a lot of special-order shoes based on his basic design but adapted to the color and fabric choice of the client. Lady Bird Johnson wore his shoes, Jackie Onassis still does and so do a lot of movie stars and models. The shoes are made in Florence, and start at about $125, depending on the fabric. Special-order shoes cost a minimum of $200, "and it is a very common thing," says Evins. The shoes that go with the inaugural ball gown have the same embroidery motif on the front and a totally beaded heel.

Judith Leiber was so afraid the white satin handbag she made for Mrs. Reagan might be soiled from sewing machine oil that she made two. Both are shirred white satin with silk straps; one has a rock crystal scarab surrounded by rhinestones ($400), and the other is the same shape with different beading ($350). Leiber and Reagan together decided that a Louisiana alligator handbag in a classic square shape would be most suitable for daytime use. (The Louisiana alligator is no longer on the endangered species list.) Neiman-Marcus has two of these bags in stock for $1,700 each. s

The amount of money the Reagans personally spent on the inaugural wardrobe, tallied from the minimum or maximum viewpoint, is high for a personal wardrobe. But it is not out of line with what the wife of the president of France might spend. "In fact, one should think of it like a coromation," said a Washington woman who buys top designer clothes.

"Spending a lot of money [on clothes] has to have some proportion to what your resources are," says Philip Miller, president of Neiman-Marcus. "I wouldn't say it would be a good investment for a young couple starting out and getting their home settled to go out and spend $1,000 on a dress for a ball. For someone who is established and has an upper-level-income, I think the pleasure of fine clothing both in terms of how they feel when you wear them, how you look and how they are perceived is a real benefit."

Says Betsy Bloomingdale, a close friend of Nancy Reagan's, who has guided her on many of her clothing purchases, "You don't buy clothes like these. You collect them." CAPTION:

Illustration, Nancy Reagan's inaugural gown, designed by James Galanos