Here's a hypothetical situation, which might end up not being hypothetical at all: My landlord is in his 80s. He owns two houses and an apartment building that will go to his son ("the bum") upon his death.

I have two questions. Can a new owner sell a building to someone else and evict all the tenants? If the son does decide to be the landlord, can he raise our rents?

If you're a month-to-month tenant, your tenancy could be terminated by the current landlord or his son, the aforedescribed bum -- or anyone to whom the alleged bum sells -- as long as you get the required amount of notice, which is 30 days in most states. The same is true of a rent increase.

If you have a lease, go find the thing at once and see whether it includes a clause that gives the landlord a right of termination when he sells or otherwise legally conveys the building. The conveying business would include leaving it to his son at death. If there is such a clause, your tenancy could be terminated as spelled out in that clause -- and it may provide less than 30 days of notice.

If the lease doesn't address what happens if the property is transferred to a new owner, neither the landlord nor anyone who owns it after him would have a right to terminate your lease. You could continue to occupy the unit at the monthly rent set by the lease for the duration of the current lease and any renewals provided for under it.

One final wrinkle: If the unit is rent-controlled or rent-stabilized, you cannot be booted out solely because the premises have been conveyed or transferred to another.