Some many years ago an elderly relative managed to smoke up a house when he fell asleep while cooking some chicken livers to feed to the dog. He called his insurance guy to ask for suggestions on getting rid of the smell - actually looking just for info. The insurance guy insisted on sending a "decontamination crew" to clean things up. Fully covered under the household insurance policy.
The agent refused reimbursement for the "damaged" skillet, though.
So far as I know, the insurant rate wasn't affected, but that was another era.
A friendly realtor might also have some good suggestions. They tend to be really fussy about houses that "smell bad," and should have lots of favorites - although probably no better than have been suggested here. I do know that every house we looked at during our last relocation had the persistent smell of "simmered spices" and most had a few candle stubs (in classy holders, of course) in far more numerous places than one might expect.
The spices tend only to cover the smell. Reports are that just burning a candle or few will help to "complete the burn" of smoke particles that are still adrift and make them "odorless." Do note though that unattended candles are one of the most dangerous things found in most homes, according to the Fire Dept people.