These basements were never meant to be finished, in fact they were meant to trap moisture.

I did this a few years ago and it still looks good as new, but I recently read that its not recommended to use fix-it-all on the exterior of the home because it can absorb the moisture in the air and further rot the wood. 

The advantage of porcelain and vinyl in Arizona (as opposed to real wood), is that you don't have to worry about moisture issues (or lack thereof).

Try to focus on properties that were built after 1960The reason for this is because the foundation of the property is likely made from poured in concrete or block construction.Poured in concrete is favorable because it allows for less water penetration into the basement.The mechanicals of the property are likely more in line with today's building code.

I recently had a tenant move out. He claims that in a spare bedroom, which was hidden by a bed, when he moved the bed out he discovered an extremely raised section of the hardwood floors. The "peak" of the raised sect...

Your contractors should do a moisture reading to see if there's anything inside the walls.

They also cause a lot more moisture in the air, fogging up the mirrors a lot faster, which is annoying to live with.  

He also observed some active water penetration into the basementI am trying to figure out if it’s worth it to look into fixing it and trying to make the deal work, or if I should just keep looking for a different property.

There also should be very few (if any) piping or electrical penetrations through the fire wall, so I don't think your rodents are getting in that way. 

The home is from 1960s and never had a moisture barrier so that’s where the damage is coming from.