You should buy 'subject to a satisfactory building inspection' which you get done immediately after having your offer accepted. You get an independant architecht or builder to go over it for you and point out the problems you have already noticed.
Sounds to me that it's not a very good building job and if the floors are a problem then you can bet there would be other issues too.
(advice given from Victoria, I don't know what state you are in and real estate sales laws are state bas3ed so they differ quite considerably)