How to rid an apartment of cat allergens?

[BillionthMonkey]

Help!

I rented a nice apartment recently, but realized after moving all my stuff in that it had been inhabited by a cat (or cats), who unfortunately were not there when I saw the place. I am very allergic to cats and was unable to stay in the apartment. So I had the place thoroughly cleaned, eight hours worth - the walls and floors (it's all hardwood or tile) washed with soap and hot water, and everything (including inside the baseboard heater vents) vaccuumed with a new, expensive hepa-filtered vaccum cleaner. I then tried to stay there again and still couldn't.

I have been living at my parents' place, starting some desensitization treatment, and running an air cleaner. I also have a friend staying there who says he will put my (new) salt lamp on for periods......

I plan on trying to stay there again in a few days, see if I can. Does anyone have any idea of anything further that I could do to decontaminate the place?

Thanks for any thoughts......