1. If they do this for 10 mods...

That should be easy for moderators to spot and we can then ban the user.

2. Indeed most buyers don't want to spend their time arguing. Often the price of mods doesn't justify spending time on dispute. Yes, dispute legitimacy parameters are needed and I hope we'll get them prepared soon via forums.

3. Right now we're in fact building a base for a bigger, more active community of both buyers and sellers. I would say that some of our planned changes should see more bring massive inflow of activity and more would be at stake. We will also need to improve these tools and figure out new ones to make everything work smoothly. There will always be crooks and leeches, but you're right about majority of members being legit and only willing to see things working as they should.