If it's an older place, I'd suggest getting a video inspection of your sewar. They have this rig with a video camera on the end of a snake. Costs a couple hundred to have it done, but it can show problems that could significantly affect the value of the property.
When I bought a fixer upper five years ago, I knew the roof leaked, the wiring was unsafe, the heating didn't work, and the plumbing was on its last legs. City records indicated that the house had been connected to the sewar system in the late '70s, so I figured it was ok.
I discovered about 18 months ago that the city records were incorrect, and I had a very old septic tank, and it didn't work any more. Cost me about $20k to connect to the city sewar.
I converted some space into a gun room last fall, it's great not having the kichen cluttered with gun cleaning stuff all the time!