kccaroYFZ450

I'm looking at a 1982 Yamaha XS400R Seca as my first motorcycle. It's mostly to get to work and back, as gas prices are killing me. The bike has low miles, needs a few cosmetic things, (turn signals are not attached, and will need to be replaced) it may need a new battery as well. My question is: What type of things should I look for when I get pictures from the seller? What kind of questions should I ask him? What types of things typically go wrong with these machines? I own a yamaha fourwheeler, and I'm not afraid of wrenching on my own machine. I just want to avoid having a total lemon on my hands, I want a bike that I can ride consistently, not keep putting money into. Any input would be helpful! Thanks! -Kevin