Hi I have $5000 in bankroll and I am a winning player on 1-2/2-4
I pay my bill with my bankroll.
I am staket from today. I did get $6000 from a friend and he tolt me to play to $24000 then give him back $12000.
You think this is a good bet?
I play 1-2 till I have $15000 then I play 2.5-5 till I have $24000.
If I bust I dont give him anything.
The rakeback I cashout every month and I get the rakeback to my self.
Thats the deal.
My $5000 bankroll I did have before stake I pay bills with.
What you think?

do you mean limit or no limit? a $5000 bankroll is absurdly small for playing 1/2NL as a job, let alone 2/4NL. that is a recipe for going broke in no time. heck it's probably not even enough to play .5/1 NL on, depending on how much of your winrate you withdraw.

as for the actual deal, i would take it since it is basically risk free for you. if you stick with your current bankroll and playing 1/2+, there's a decent chance you won't be paying bills with that roll for much longer.

winwin all the time (for you)

if (when) he get to 24k, he has lost 6000$. thats not winwin

Think of this from your backer’s viewpoint as calling a bet. He is investing $6000 to win $6,000. For him to win, you have to quadruple your $6000 bankroll to $24,000 before you go bust. His EV is

Backer EV = P(quadruple)*6000 –P(bust)*6000.

So clearly, if the chances you quadruple is greater than the chances you bust, he makes out. Now what is your risk? From a dollar POV, nothing. You might even ensure some profit from rakeback. You are playing with his money. However, suppose it took you a year to get to $24,000. So in the end you made $12,000 for a year’s work. But you might still be in the nowhere range at the end of a year.

It would seem to me that the staking arrangement should have some kind of time limit when at the end, if no bust or no payoff, there is a sharing with you getting the greater share for your time and skill, say 60/40.

You get to keep all the rakeback!!? GO FOR IT!!