I would look into that I bet it does cover the physical buildings. 

I was thinking of asking for a key or having the unit owner sign a document releasing me from any liability or damage that is caused by my inability to access the utility room.  

Read the fine print in the foundation repair contract: Damages to the property, interior and exterior as a result of the foundation movement are not covered, during and after works completion.

One issue that we've ran into twice is that our limit on mobile deposits is $2,500, we have had two checks that were bigger than that amount and had to go to a physical location to deposit them.

Be sure there is no damage and like @Justin Fox said, if the neighborhood can't support your improvements then don't do it.

During the last visit we noticed some damages that were not visible previously. 

There are signs of some water damage. 

It really just depends on the amount of damage.

Based on my experience in the market, my suspicion is that a duplex at this price point is probably in a less desirable location or else is in bad physical condition.

I have a property I am trying to sell and the buyers want to close 6 months from now when they are good and ready to move in and would like to keep their inspection contingency until then in case there is any spring water damage or something else happens between now and then.