It looks like you might need more bucks than me!
In fact it looks like you only have 1 hero at skill level 80/80/80/80 (Mauler).
On a really really really conservative basis assuming you want to skill up your remaining 62 out of 63 heroes from 75/75/75/75 to 80/80/80/80 like your Mauler, you will need approximately:
x4 skills per hero
x 264,000 bucks to skill up from skill level 75 —> 80
= 65,472,000 Bucks
So YOU need more than 65 million Bucks RIGHT NOW to level all your heroes from skill level 75 —> 80.
In truth you probably need MORE than that, since only a handful of your heroes are even 75/75/75/75, most of them are not even levelled that high.
And to drive the point home, YOU would need this right now. Not in 100 days or 25 days.
So maybe we don’t talk about me, we talk about you (since I guess you are less controversial).