This is the final outcome that i've decided.
I'm not great at Maths I only got a C when I did it at GCSE in secondary school so if there is any mistake in the calc's notify me immediately.
The skills gh0st levelled from the screenshots he provided.
1) Thieving
2) Strength
3) Attack
4) Defence
5) Hitpoints
6) Agility
Now this is what the starting levels were for those 6 skills
1) Thieving 53
2) Agility 35
3) Attack 64
4) Defence 33
5) Strength 84
6) Hitpoints 78
These are the latest stats that gh0st got on that account
1) Thieving 62
2) Strength 94
3) Hitpoints 89
4) Agility 36
5) Defence 78
6) Attack 89
PROPOSAL 1: You refund him 5M and you gain him all of this exp on a new account that he makes. (You pay for supplies too) If you bot it and it get's banned you'll get IP'd.
Ok now let's calculate the EXP difference. (Using Tip.it skill calculator)
Thieving:
Let's calculate the diff 333,804 - 136,594 = 197,210 Thieving EXP that he gained so basically you're gonna get him to LVL 56 = 197,210
LVL 53 = (136,594 XP)
LVL 62 = (333,804 XP)
Attack:
4842295 - 407015 = 4435280 = Lvl 88 attack you'll need to get him
LVL 64 = 407,015 XP)
LVL 89 = (4,842,295 XP)
Strength
7,944,614 XP) - (2,951,373 XP) = 4993241 = 89 STR you'll need to get
LVL 84 = (2,951,373 XP)
LVL 94 = (7,944,614 XP)
Hitpoints:
lvl 89-lvl 78 = 3213095 EXP = LVL 84 HP
78 = (1,629,200 XP)
89= (4,842,295 XP)
Defence:
TLDR; 1610953 EXP diff = LVL 77 HP you'll need to get
33 = (18,247 XP)
78 = (1,629,200 XP)
Finally Agility:
2409 EXP diff = LVL 14 agility you'll need to get
35 = (22,406 XP)
36 = (24,815 XP)
Ok now that's option 1. If gh0st agrees with this you can do this if you want to
Option 2: Repeat as option 1 but you'll pay a servicer to complete it. Who chooses the servicer? Well you and gh0st will have to decide on that
Option 3: you and gh0st both decide what the account is worth with the current stats and you refund him that amount (probs the best of proposed options)