J. Francis Harts III doesn't like the name of a person who would be protesting a tax assessment that increased from $38 to $40, especially in Georgetown. Most of us would feel fortunate to be so blessed these days. But Harris says the new assessment means that the taxes on his Georgetown property will rise from 76 cents to 80 cents this year. Harris owns an undeveloped sliver of land, 6 inches by 100 feet, alongside the Suter's Lane town houses that he had a hand in developing some years back. It was a left-over strip to which he took separate title. "I realize that all values are going crazy but this is too much," Harris said, "My property has scant intrinsic value. It's just an oddity and it costs the D.C. government 13 cents to notify me that my assessment has been raised and that my tax will be 4 cents more this year." Harris now is a member of the Vicki Bagley realty staff in Georgetown.

Everyone knows that single-family houses are appreciating in value these days and that $80,000 prices are not unusual. But interest rates are rising and they figure to deter some possible purchasers. Ken MUrphy, director of the new homes divisions of Long & Foster, Inc., realtors, has devised a chart showing the annual, monthly and daily appreciation on houses (priced at $30,000) to $100,000 in increments of $10,000) at the national average rate of 8 per cent annually promulgated by the Department of Commerce. On that basis, an $80,000 house appreciates $6,400 annually, $533 a month and $17.78 a day. This is how Murphy and his people combat prospective buyer reluctance to pay $23.35 more per month on a $64,000 mortgage when rates rise 1/2 percent. "The interest rate increase is insignificant in comparison to the average inflation on new homes," Murphy said.

If you have a proposal for the restoration of the Willard Hotel or an adjacent 35,100 square feet of commercial ground on Pennsylvania Avenue between 14th and 15th streets NW, there's still time to do something about it. The Pennsylvania Avenue Development Corp. has been sending announcements around the country to tell interested parties that proposals are welcome. The corporation is also inviting proposals on a 123,000-square-foot commercial site on Pennsylvania between 13th and 14th streets. Locally, the Oliver T. Carr Co. is known to be interested in the Willard site, which the PADC acquired after years of negotiations. Prospectuses on any of the three sites are available from PADC, 425 13th St. NW, D.C. 20004, for $25. Submissions of proposals are due July 1.

PADC is a federal agency created by Congress to plan and guide redevelopment of the "ceremonial" Pennyslvania Avenue corrido r between the White House and Capitol Hill.