If so, you can test each unit separately, as it seems obvious that the first floor leak would be from the second floor, but water is a tricky situation.For the roof, I would certainly get several groups out to let them diagnose the issue and bid the resolution.  

That being said, I don't think the bank is going to be sending folks to peep through your window to confirm you live there... but you obviously still shouldn't do anything misleading, hypothetical or not :) If you have utilities or some bills in your name headed to that address, that would adequately show a proof of residence to some capacity. 

Keep in mind many could not pay cash even if they wanted to so leverage is a must especially those starting out obviously.

Obviously you will still need to research if you need permits and if it is allowed.

They are obviously just trying to get one over on you.

The roommates have issues with this, obviously.

Obviously this is dependent on your local area, saturation and quality of product.

They obviously want to be helpful, but they are setting both of you up for an ugly end.

I was like no snit but I am not reducing the price as that was clearly visible when you walked the property (which they did)If there is an electrical issue that comes up that is a problem - sure I can fix it or give some $ to get it resolved but for blatant obvious things I do not negotiate as it should have already been part of the offer

The "sneaky duplex" phrase sounds to me just like "sneaky tax evasion" - it's great to get something illegally until you are caught.The screaming obvious action for you here is to call your town and ask about the property.