I am by no means a plumber, but I had a similar problem at my last house. There were no additions, just one day got that hammer sound when running water. The problem was a bad, or failing, pressure regulator. I had a plumber replace it and everything was good.
John
I do them myself - the dealerships hire the guys who can barely turn a wrench to do oil changes. It doesn't take me that long, plus it gives me a chance to inspect whats going on underneath the car. Oh, and I enjoy doing it too.
I had a tv in the garage at the last house and in this one. It's a little 12 inch tv, but I just use it to listen to a ballgame when I'm in the garage.
X2 on checking the birdcage for rust. Remove the kick panels and look at the body mounts for rust - easy to do. Also remove the trim around the birdcage - easy to do and owner shouldn't have a problem with it - to see if there is any major rust.
Nothing you can do without disassembly. Carefully clean the surface of the block so you have a good surface for the heads to sit on. Preparation is your friend here - blocking holes so gunk doesn't get in. You could pull off the oil pan and have a look at the bottom end, but that quickly gets...
Here's mine - it's a single bay, 16x25. It has a hip roof and the ceiling is vaulted. This is a composite of seveal pics, so you have to overlook the distortion, but hopefully you'll get an idea of the inside.