Looking for suggestions to fix floor on short term IP

Hi All, I am looking a 2-3 Townhouse development site, the site has a 3-4BR house on it in need of some work.

With the market the way it is, I am hoping to freshen up the house an rent it out til the market recovers and I have enough $$ to demolish and develop probably in about  2-3 years.

I am pretty handy and can tackle 99% of the work that is needed, the only issue I have is the floors they are unlevel in 4-5 rooms.

Does anyone have any suggestions on the most cost effective way to sort this out? 

I was thinking of removing the flooring and replacing stumps etc, then putting down some yellow tongue floor and finishing with vinyl tiles in the wet areas, carpet in the lounge/bedrooms.

thanks
Joe