Cat allergy - how to clean our new home?

[Blu]

We are moving house into a home previously occupied by a cat.
DS and I are allergic to cats - will it be ok if we mop all hard floors and steam clean the carpets?

Although I have it in my head that cat allergy is caused by the proteins on the fur (left by these lovely clean animals licking themselves with thier saliva), and that heat doesn't neutralise proteins?

cant you get cleaners in before you move in?

Unfortunately not - we're moving in a chain, our stuff has to be in the van by 2pm, the vendors vacate at 2pm.
I have steam cleaners coming the following day - we will have to rely on a good pull-through with the Dyson and anti-histamine until then.