Those of us for whom fantasy is a once-a-year diversion can find the search for a Halloween costume -- or even idea -- exhausting.

Fortunately, the Washington area is loaded with stores that rent and sell costumes and accessories with prices ranging from $1 to $150, give or take a feather boa. You may be content dressing as a southern Belle or a pirate, but consider the possibilities of going as a bunch of grapes (Costumes Creative) or a 6-foot rabbit (Barry's Magic Shop).

If you rent a costume, count on spending about $35 -- and up -- and remember that (a) you'll be lucky to find something you like if you wait any longer than this weekend (many costumes are already reserved), and (b) you'll be expected to leave a security deposit. As a rule, the more convenient a rental store is to your downtown office, the higher the fee. Don't ignore suburban shops which often offer wide selections at more reasonable prices.

Also, don't assume that renting is cheaper than buying. You may well be able to buy a cape, fangs and all the necessities for the ever-popular Dracula costume for about the same cost as renting it -- including a tube of vampire blood ($1). And then it's yours to keep (particularly useful if you experience a personality transformation).

Inexpensive kits -- combined with a leotard and tights -- can turn you into a kitten, bunny, mouse, devil, clown, angel, butterfly, bumblebee. Masks and other accessories, combined with things hanging in your closet, can turn you into a pirate, hobo, matador, call girl, gambler, French apache dancer, punk rocker, flapper, fairy, frog prince, princess, sailor, hunchback, jockey, werewolf (hair-faces and hands combine particularly well with business suits/police uniforms), Raggedy Ann/Andy, witch, sheik, cave man/ woman, jester, mummy, spaceperson.

If your costume idea is inspired by a movie (as many of them are), you may have trouble finding what you need to achieve the perfect look. Thanks to "Raiders of the Lost Ark," Indiana Jones should pop up at more than a couple parties and you'll be hard put to find bull whips this week: There's been a run on them and leather jackets.

Certain costumes have already sold out in many stores. Zorro was among the first to go in one store, followed by Dracula, Darth Vader and the Roman soldier. Women have already bought up many of the traditionally sexy costumes: harem dancers, French maids and Playboy bunnies.

"We've had about 50 calls for Scarlett O'Hara," reports the owner of Fantasy Costumes, "and a lot of calls about knights in shining armor." Among men, horror characters are tops in popularity, particularly vampires and that archetypal schizoid character, the Incredible Hulk.

"Last year," says one store owner, "political masks didn't sell well at all. This year a lot of people have bought Reagan masks. Many couples are dressing as Reagan and Bonzo, and one girl is putting together a Nancy Reagan costume with the slogan, 'Let them eat catsup.' "

Imagination and a sense of fun can take you a long way on Halloween. One of the giddiest evenings of my life was spent as a gum-popping roller-derby queen, in tights, roller skates, a borrowed football jersey with a felt "Wanda" on the back, heavy makeup and a scaggy wig. Though I wore no mask, even my own husband didn't recognize me and I felt liberated by tough-girl anonymity.

One Washington woman last Halloween made herself as yellow as possible with clothing and makeup, covered her body with the Yellow Pages and hung a sign around her neck: "Let your fingers do the walking."

Halloween is the time to honor your fantasies. Forget about your boss, deadlines, quotas, housework and let the ideas here help you play make-believe.

Not invited to a party? You can always go trick-or-treating.

Next week: Halloween makeup.