IN LIGHT OF consumer complaints about high-pressure sales tactics, and recent reports of two time-sharing project bankruptcies that have left nearly 6,000 buyers wondering whether they'll ever get their money back, federal and industry experts urge prospective purchasers to proceed with care. Before buying time-share property, they suggest you:

* Study the resort and its location, and spend time vacationing there if possible. Check for quality construction, durable furnishings and good interior and exterior maintenance. Talk to management and present owners.

* Find out all you can about the builder/seller. If the property is mortgaged, when is it to be paid and by what means? Ask when sales began and how many sales have been made. Get bank and local references and check them out.

* Carefully evaluate any investment claims made by the seller. You're not buying a great investment opportunity, but the right to future vacations at today's prices. Even if a unit increases in value, a one-week deeded time-share will give you a return of only 2 percent of that increase.

* Be certain no one can disturb your right to use the property for the period for which you contract. This should include protection against any default by the builder/seller on present loans and against any future encumbrances on the building.

* Consider whether you'll be able to use a time-share facility regularly. If your vacation plans are subject to last-minute changes or vary greatly in length and season from year to year, this could be a problem.

* Realize that the total cost of your time-share includes expenses such as finance charges, travel costs and annual fees for maintenance that may well rise at rates that equal or exceed the inflation rates.

* Do not act on impulse or under pressure. Have an attorney review any documents or legal requirements you are unclear about before signing.Ask about a "cooling off" period.

* Be sure everything the salesperson promised orally is written in the contract.

* Remember that exchange programs usually can't be guaranteed and that there may be some limits on exchange opportunities -- such as the requirement you make requests far in advance. If your resort is not in a desirable location and/or is not well-run, your chances of matching are diminished.

* If you are buying a time-share on property where the facilities have not been completed, get a written commitment from the seller that they will be finished as promised. One way to protect your finances during this period is to have the money held in escrow until completion.

* Find out if the builder/seller is a member of the National TimeSharing Council, which requires members to meet certain standards of ethical practice.

Resources:

* For a copy of the Federal Trade Commission's free time-sharing fact sheet, write for "Ten Time-Share Tips," FTC Bureau of Consumer Protection, Sixth Street and Pennsylvania Avenue NW, Washington, D.C. 20580.

* The National Time-Sharing Cuncil of the American Land Development Association can provide more information about time-sharing and offers a "Consumers' Guide to Time-Sharing" for $1. Write them at 1000 16th St. NW, Suite 604, Washington, D.C. 20036.

* "Resort Time-Sharing" by time-share marketer and developer Keith Trowbridge offers an in-depth, but admittedly partisan, view of interval ownership (Simon and Schuster, $11.50.)

"Time-Share Vacations" by Phyllis Spencer provides a good overview for consumers (Everest House, $7.95 paperback).