I owned a Peavey Mark bass head. I forget which model it was; 3 or 4 but it was still a decent head and lasted many gigs with my bands when I was a young warthog. I attached a 15 and 210's to it and it sounded killer. I also tweaked a few things on the cabs so it would sound better by adding a higher rated horn. There was an option to split the high end and the low end and it suited well with my style. It is a decent head and very rugged. Traveling throughout the state of N. Carolina I'll say Peavey made a good product for the money that sounded well.
P.S. Try to talk the price down. If it's used, which more than likely it will be than look for wear and tear, knob issues, scratchy pots, rusty/dirty metal edges or areas. It's a very good idea to try the amp out first but for pricing purposes look for reasons to cut the price. Since I've traveled to quite a few different countries one thing I learned is haggling and looking for reason to mark the price down. They are trying to feed their mouths as well as a family and need to get rid of it, eventually they'll get it off the shelves with a lower price than keeping it collecting dust and wasting space for more or better gear at a higher price. You get my drift?