I think Refine already has potential self-synergy if you rearrange and remove text. So my thought is this:
+1 Action
You may name a Supply pile. Cards from that pile cost $1 more this turn.
You may trash a card from your hand to gain a card costing up to $1 more than it.
This already stacks with itself. Non-terminal, I guess it can cost $5? Maybe too cheap for a non-terminal Remodel with stacking power, really not sure on balance or if $6 is balanced or if it's just crazy.
I think I was reading two versions back-to-back and got them smashed together in my head, and then I didn't reload the page and this version more or less was already given. Overall, it's kind of similar to that new Workshop variant that lowers costs, but for Remodel, so it's fair I think. Non-terminal at $5 remains questionable for me but idk without testing.