Great design and implementation. Smooth tutorial and fair transition between parts. Really nice work from y'all!
Feedback/Food for thought: I thought I am buying the chests from adventurers. So maybe instead of buying the keys I'd switch that to a "buy" mechanic. The character would have great lockpicking skills. For further development you could extend the shop to broaden the amount of honorable adventurers that come to your place. Maybe some adventurers also come for just the opening service and even pay you! (Especially great if you run out of money). To give the loot variety you could have some groups that rotate in and if you sell items they want from the chests directly back to them, build relationships. I'd be happy to see this game going further.