To acquire equipment for an adult prom, check "Rental" in the Yellow Pages. Places and prices listed here are only a sample; comparison-shopping may save you money.
* Outdoor Dance Floor: 6 by 12 feet, delivered and installed, $44; topped with a 16-by-16-foot canopy, another $200. A-Plus Rental Center, Springfield, Va.
* Champagne Fountain: Circulates 2-7 gallons, $22 to $35. A-1 Rental Center, Annandale, Va.
* Mirrored Ball: Large, 16-inch, $12. Small, 10-inch, $8. (Spotlights, extra charge.) AAA Rental Center, Landover Hills, Md.
Makings of a prom-nostalgia night:
* Corsages: In the right color. Chances are that the presenter and presentee share a breakfast table. The message can be conveyed over orange juice that the dress of the evening is RED.
* Authentic Dress: Usually found by searching one of the many old-clothes shops. Among them: Value Village, 4618 14th. St. NW; Blue Moon, 2435 18th. St. NW.; Classic Clothing Co., 1015 Wisconsin Ave. NW., and 3701 Benning Rd. NE.
* Potted Palms: To hide behind and steal a kiss, available from, among other places, Flowerentals of Washington, 4713 Wisconsin Ave. NW. Artificial plants, 5- to 6-feet tall, $15, plus pick-up and delivery, for rental up to a week.