AI question: retrofitting

[Ragnarok-X]

i guess i have to go into detail: My mod has several weapon branched, like gauss weapons, sonic weapons, laser, plasma and so on. Each tree has about a douzen levels, and each level enhances "your" basic weapon by one level. Each 4th. level allows/enhanced a medium weapon, and the 10th. level makes a advanced weapon from that branche available. While the cost for lesser weapons increase by approx 10-15 % per level, one medium weapon costs as much as about 5 ot 6 lesser weapons, and one advanced weapon cost about 3 medium weapons. So the retrofitting wont work ty anyway !