HUD Home won't turn water on for inspection

[Richard Bradshaw]

I am under contract to purchase a HUD property that has been vacant for about 2 years. I am having an inspection performed next week but they will not allow me to turn on the water. I do know that it has failed a pressure test already.

There are no signs of leaking plumping anywhere in the home. I have a plumber coming to do another pressure test next week to try and find the problem. 

My question is, is it too risky to purchase this home without having the water turned on and knowing the exact problem? 

Has anyone ever ran into this situation? What are some of the costly issues I could run into if I purchase?