Please everyone post your sale prices for various builds and levels. I’ll start:
5/5/0, level 63 - 4500 iso and 250 HP.
edit: Updating title
5/5/0 Level 103, 22701 
, 750 
I’m pretty sure it’s just a function of level (which is itself a function of covers) so build doesn’t matter.
Just out of curiosity, if GrumpySmurf would level his Rags from 63 to 103 would he be able to get an increased amount of HP upon selling? Might be worth it if you need the HP and can spare the Iso-8.
I don’t have Rags myself, the only 3* I don’t have at the moment, but it could be interesting to see if maybe it would be worth levelling and then selling MNMags when his change/nerf comes along. I might just sell him (MNMags) for the HP and build myself a new one if needed. Cheap tactic, I know, but hey… every couple of ‘free’ HP is more than welcome, even HP in exchange for Iso-8… 
5/5/0 Lvl 95 625
17813
Here’s the table I put together from selling Sentry last time, covering all sale price increases up to level 90:
51 2500 250
54 3000
56 3500
59 4000
62 4500
64 5000 375
67 5500
69 6000
72 6685
74 7659
77 8699 500
79 9803
82 10975
85 12211
87 13514
90 14881 625
Basically, for hp it’s 250 at level 51 and 125 hp for every 13 levels after that. For ISO it’s slightly less than half of the cost to get to that level. Looks like Lerysh’s line for level 103 conforms to that pattern.
Pretty sure the answer there is yes, which is also why you should save any MNM covers you get. 2 covers of the same color adds up to level 22 which sells for 50
That’s part of the reason I’m asking. I’m absolutely going to level him and trade it for HP, it’s just a question of how high and how much.
4/5 Level 88: 13,514 iso, 500 HP
So then 103 is 750, 116 is 875, 129 is 1000, 142 is 1125, 155 is 1250, and 166 is still 1250?
I can max him to 140 for 103k, so looks like the one blue cover would be worth 125, but need 3 to get to 1250. So basically 40-45k iso for 1000HP. I’ll take it.
edit: because the Devs are hilarious I’m sure Rags will be featured in PvP sometime soon, so may hold off a few days, level him for the event and then sell him
5/5 lvl 120
36,403 iso
875HP
I think I can confirm level 166 is 1250 HP from when Sentry was for sale on buy back.
5/5/0
L78
8699
500
4/5 level 127 (max possible for me)
40907 iso, 875hp
5/5, level 140
53316 ISO, 1000 HP
I think it might be because of the covers, sentry was 13 covers and rags is only 10
Sell price is a function of levels. To get to level 166 you need 13 covers. Level is a function of covers. So in an indirect way sell price is a function of covers, but a 13 cover Sentry at level 40 won’t sell for the same as a 166. Just as a 5/5 103 rags is different from a 5/5 63 Rags. All it cares about is level.
If anyone needs confirmation… I just leveled my lvl40 rags to lvl51 and the sell price jumped from 500iso/0hp to 2500iso/250hp
If you have any data on buyback prices, please post it in mischiefmaker’s spreadsheet here: