You couldn't pay me to spend a night in that house alone much less live there. Whether it's haunted or not, I wouldn't feel comfortable in a house where a mass murder happened.
As far as it really being haunted, I don't know. I was cleaning out my grandparents house after they passed away and I heard a door open in the back bedroom. I told myself it was the wind even though I knew there were no windows open back there. About 10 mins. later the door slammed shut so loud that I about jumped through the ceiling. I got the hell out of there so fast that I forgot to lock the front door. My mom is a lot braver than I am because she lives there now and said that she hears strange noises back there too. I don't know what it was that day, I just know that big heavy wooden doors don't open and close by themselves.