You never know what you'll uncover behind the stone, or what damage could be done to the exterior sheathing if the stone is difficult to remove.

My concern is getting into this and uncovering some much larger (and expensive problem) or running into a problem at re-sell?

@Daunte FlowersBoth are important, however having the skills to uncover and create profitable transactions has much more value and extremely rare.

Do you uncover needs of the seller through probing questions?

The church, I uncovered was not a sole property and included houses and lots directly adjacent, which if purchased in whole would be sold at a discounted price.

They're probably chattering about your Un-covered vent out in Europe.

In contract with a house, had the inspection complete and it uncovered that some footers need to be replaced (sitting on cinder blocks and on soil) and the main beam has a slight bow in it. 

Now if you had a workers comp policy, then you would end up covering any worker you hire; a year end audit would uncover that you had employed workers who did not carry their own coverage and so you would be paying additional premiums for the time (and tasks) that they worked for you!  

A persistent and creative buyer who is willing to do the leg work should always be able to uncover good leads.

I uncover most problems right there.