I'm a bit biased, but get a home inspection. It will be worth the $$ saved on knowing what you are getting into.
Mold is a serious issue if it is bad enough, no guesswork, getthe facts on WHY there is water.
Only a Professional will tie all the systems together and give you a good idea what your up against. Some you will not be able to see until after you open the walls up.
I have been remodeling for 25 years, and been an Inspector for 15, I have seen things that never make sense or even thought was possible with a home. And spent plenty of $$ to fix isssues that looked good until we got into Pandoras little box of goodies.
American Society of Home Inspectors, ASHI
for a good Inspector, find one that deals with environmental issues with a home.