I'm so sorry about Pete's kids. I wish he had written a will. I do hope that you didn't pay for the work on the house yourself, since they are reaping the benefit.
I have found that plain old vinegar and water does the trick for cleaning hardwood floors. If you use other products, they tend to "gum" the dirt into the wood and seal it there. (Same product for tile!)
A house as old as that either has the original hardwood, which would be wide planks, or the original wood has been replaced (maybe several times.) You can only re-do the hardwood just so many times before it needs to be replaced. If I were you, I would want to know the particulars about this floor before buying the house. How old is the floor? How many times have the floors been re-done? What kind of wood is the floor and what kind of stain and sealant did they use?
Maybe you can't get that info, but I'd try. You can also ask a floor specialist to come in and give you an opinion. It would be worth paying for that.
Don't forget that you need proper padding under your throw rugs and oriental rugs. That's really important.
Hugs!