I think there needs to be certain rules about taking advantage of builders because a lot of people tend too and this will ruin the future of ecocitycraft as many builders will choose to leave and not come back due to being taken advantage up by other users
We honestly can't do anything about that. If a builder is smart, they most likely won't fall for much. It is their choice to quit.
If you see it happening, tell the builder. Simple, right? This isn't something the server can fix. It's only something the community can fix.
-1. This whole we need to treat everyone like they can't think for themselves attitude is rediculous.
You mean like the scamming/attempted scamming rules we already have? Of course some things don't count (underpaying for certain goods) but in those cases... once the builders find out (which they'd need to do to even know to file a report in the first place) they simply know that next time to get more money. I really don't want to draw a line where 35% below market price is competitive and 40% below market price is taking advantage.
The only solution to this is to be proactive as possible about informing any builders you see struggling and preventing these circumstances as you see this happen. Reducing builder ignorance via knowledge will fix this. It is already part of the rules that if they can prove it, this is not legal to do. The problem is most builders don't figure out how to properly record evidence until later. So again, knowledge is power.
Though I might agree with the general principle, I can't refrain from asking a question: could you be more specific? I mean more specific about both the problem and the solution.