In many cities -- large and small -- apartment hunting has become a grim business.

"We're entering a crisis situation," says a top government housing official. He's referring to the fact that most areas now have less than five percent vacancies for apartment rentals.

"And, when you do find a vacancy," says Woody Widrow, editor of Shelterforce Magazine for tenants, "you usually get something that's very expensive or substandard."

Government housing officials and tenant association leaders say the squeeze on apartment renters is caused by the fact that it's just not profitable anymore to build rental apartments.

The financing costs are sky high, land prices are out of sight and operating costs are top heavy. developers can't charge enough rent to make buildings profitable.

If they build anything, it's usually a condominium. And, landlords who own existing apartment buildings are rushing to convert them into condominiums so they can get out of the money-losing rental business with a tidy profit.

Other landlords who own low-income rental housing are abandoning buildings when major repairs are called for. They have wrung out all possible profit and want to take a loss for tax benefits.

With this kind of squeeze on, it's little wonder that rents are moving up steadily to the point where you have to pay through the nose for a two-bedroom place you wouldn't have bothered looking at five years ago.

There is some rental building going on, but it's mostly government subsidized (Section 8) housing for people with low to moderate incomes. And, wouldn't you know it, finding one of these rent subsidy bargains is akin to winning a lottery.

There is also some activity in building for the elderly. Any older person who has been forced out through a condo conversion or raise in the rent should check to see what's available.

Usually, some religious group or civic organization gets federal backup funding to build housing for the elderly. Your local housing authority or government agency on aging should know if there is anything available or anything in the planning stage. It's also a good idea to check local religious organizations to see if there are any plans for subsidized housing for the elderly.

Meanwhile, you might want to join an area tenants' association if there is any plans for subsidized housing for the elderly.

Meanwhile, you might want to join an area tenants' association if there is one available. Or, you might want to help form an association.

When thousands of tenants have been forced to leave their apartments because their buildings were converted into condominiums, the publicity triggered the formation of tenants' rights groups which work on local governments to control the spread of condominium conversions and to control rents.

Q. We have some old baseball cards and some toys that date back many years. Are they worth anything to collectors? Where can we sell them?

A. The cards and toys may be worth some money, depending on their condition. It all comes down to how much a collector is willing to pay. You have to look through collectors' books and magazines in your library for ideas.

Or you might want to get in touch with various collector publications with letters to the editors about your items. You may get some advice, or you may get an invitation to put in a small advertisement. You can get a "Collectibles Directory and Sourcebook" by sending $5 to: SourceBooks, Box 14141, San Francisco, Calif. 94114. It has the names and addresses of every conceivable magazine, journal, club, newsletter, price guide, auction and association known to the experts.

Q. About bargains in plane fares: It's true that some airlines have special fares, but there are a lot of catches. Also, once you get where you're going, you find that hotels, restaurants and other things are so expensive. Where can one go for a vacation that doesn't cost so much?

A. Are you ready for this? Get a tent. Go camping. Or, find a farm, get a horse and see the countryside. This may sound crazy to someone who is used to planes, hotels, motels and restaurants. But, you can save a lot of money with a tent or a room in a farmhouse.