There are every-month, garden-variety mortgages that most homeowners pay. And now there's the one that Jay Rockefeller pays.

While the average Washington-area homeowner labors under a $151,311 mortgage, second highest in the nation, Sen. John D. "Jay" Rockefeller, D-W.Va., last month stepped into the yoke for $15.3 million when he refinanced his home at 1940 Shepherd St. NW. The house, a Southern-plantation-style manor on a 15.9-acre site, is located in the Crestwood community near Rock Creek Park.Rockefeller declined to comment on the refinancing or the terms involved.

Detter added, however, that the estate, known as The Rocks, built in the 1920s, has required substantial renovations.

"The refinancing included these improvements and additional upgrades and security measures," Det-ter said.

The monthly payment is almost certain to be weighty on a loan of that size.

In fact, assuming Rockefeller has a standard 30-year mortgage at a 10 percent interest rate - fairly standard terms for many conventional loans - his mortgage payment is probably about $134,000 a month, according to accountants asked by The Washington Post to consider a loan the size of the one secured by Rockefeller.

In other terms, Rockefeller may face monthly payments that are more than 100 times higher than the $1,201 a month that the accounting firm of Kenneth Leventhal & Co. recently found that the typical homeowner in the Washington area pays.

The $134,000 would be nearly the equivalent of purchasing two homes for cash each month in Charleston, W. Va., where the median home price is $73,000. The median price in the Washington area is about $130,000.

But heavy housing expenditures have their compensations.

Again assuming Rockefeller has a fairly standard mortgage arrangement, he could legally enjoy a quite substantial mortgage-interest deduction, according to local accountants and financial planners.