DEAR BOB: Week after week, you tell people all sorts of good ways to finance their property purchases with little or no cash. Where can I learn more about this real estate leverage? All these real estate millionaires keep these secrets so they can fatten their bellies and keep the rest of us in ignorance. Crespin R., Gaithersburg.

DEAR CRESPIN: Successful real estate investors, contrary to your opinion, are extremely generous in sharing their finance knowledge. Here's a list of good books on the subject: (1) High Leverage Real Estate Investments: Inside Secrets of Using OPM, by Oliver Ray Price (Prentice-Hall), (2) How to Go from Rags to Riches Fast with Sound Real Estate Investments, by J. Brad Lampley (Prentice-Hall), (3) How You Can Become Financially Independent Investing in Real Estate, by Albert Lowry (Simon and Schuster), (4) How Real Estate Fortunes are Made, by George Bockl (Prentice-Hall), and (5) Essentials of Real Estate Finance, by David Sirota (Real Esate Education Co.). These books and others on real estate finance are available at larger libraries and bookstores.

DEAR BOB: If we sell our present home, we will have about $40,000 profit. When we use that new $100,000 tax exemption, can we save the other $60,000 of our exemption for later use? Conwright M., Rockville.

DEAR CONWRIGHT: No. You can use the $100,000 tax benefit on a home sale only once per lifetime. Any unused portion is wasted.

DEAR BOB: We bought a home last October. The seller said she was selling because she needed cash to pay medical bills. We later found out she was selling to buy a bigger house. Should we sue for fraud? Joe M., Wheaton.

DEAR JOE: No. While it's wise to ask the seller the reason for the sale, the true reason is often concealed. Unless a property defect was the reason for selling, you probably weren't harmed by the untruth. Forget it. You've got more important things to do.

Readers desiring the report, "How to Sell Your Home With or Without an Agent," should send 25 cents plus a STAMPED self-addressed envelope to Robert J. Bruss, P.O. Box 6710, San Francisco, Calif. 94101. CAPTION: Picture, NEW IN ANNAPOLIS--Viewed from the Severn riverfront, these are some of the recently completed Chesapeake Landing condominium town houses that have been developed by Jerome J. Parks. Priced from $165,000, the cedarsided dwellings are located in the Eastport section of Annapolis.