Yep. You need to ask. You can show him (them) GJ shops and say how cool it would be to keep the shop in the family. Is it still a working shop? Do you (or did you) spend time there as a kid or now? Would you run it as a personal shop or business? Are there other siblings who have an interest in it? There are lots of things to consider. Those block walls, windows and "stuff" in the yard sure do bring back memories!
We never thought we'd have a chance of buying our 1930s auto shop, but we asked and the answer was "yes". Ours was in much worse shape than that building. It can't hurt to ask.
Chris