Good advice from Jed.
I'm not trying to talk you into buying the house, but just be aware that some problems that buyers consider serious or "horrible" really aren't. Most structural problems, for instance, are fixable, and for far less than most people think. Mold remediation is another one of those issues that scares a lot of people, but really doesn't have to. There are professionals out there that can correctly fix both of those problems...again, often for far less than you might think.
A quick example: I took a look at a house a while ago. It needed some rehab, but really was mainly dirty, a bit outdated, and a bit shabby. I guessed it would cost about $40,000. Not insignificant, but not huge for a house that, fixed up, would sell for about $600,000. I then went to another open house and started talking to the agents there. I mentioned to the agents at the second house that I'd looked at the first, shabby house. They asked me how much work I though it needed, and I answered--about $40,000. They told me that another buyer--just a regular, retail buyer--had been through earlier. That earlier buyer had also visited the shabby first house. And at the second, she told the agents there that the house needed "at least $100,000 in repairs." Point is: Before you assume a problem is horrendous or unfixable, call in experts. The answer might surprise you.
Hope that helps.