Condominum owners and apartment dwellers should not be lulled into thinking that they have no security problems simply because they live in a large building, one housing executive warns.

Vacation-bound high-rise dwellers should prepare a security checklist in plenty of time to allow for proper precautions, says T. Donald Sally, vice president of Bair & Warner and general manager of the company's property-management division.

"It's a mistake to think you have no security problems just because it's more difficult to spot an empty apartment, especially in a large building, than an empty house -- or because the building may have a doorman or security service," Sally said. "Everyone is vulnerable."

Sally suggested these points for your security checklist:

Notify your building manager and a trusted neighbor that you are going on vacation. Let them know where you can be reached and when you expect to return. If a friend will be coming in to water the plants or feed the cat, be sure to tell the building manager, or your friend may be detained for questioning.

Check with the telephone company about vacation shut-off service. You may be able to save money if your phone will not be used while you're away.

Notify the post office to hold your mail while you're away, or arrange for a neighbor to pick up your mail daily from the lobby mailbox. Mail left accumulating can tip off burglars.

Stop deliveries of newspapers, milk, juice and other items, or have a neighbor pick up these items. Notify the building manager or neighbor if you expect any deliveries while you are gone -- to avoid phony deliveries, for one thing.

Put your valuable jewelry in a safe deposit box. If you don't already have a list of all your credit cards, make one.