Right now price based on item colour regardless of how many stat lines.
My suggestion: rerolling price must be based on number of stat lines not on item colour.
For example:
1 stat - 100 nucle
2 stats - 200 nucle
3 stats - 300 nucle 10 sierra
4 stats - 400 nucle 20 sierra
etc
81 sierra powder is TOO HIGH for rerolling 1-3 lines, plus to this stats have big range (10-130+ loot chance for example)