What's the meaning

of ballin on here?

"...So as we are leaving me and another guy are deciding what we should tip, we figure $120 between the 3 is reasonable so we both put our 2 x $20 flat on the side. Then our tight-ass douchebag friend comes in, who loves to be ballin on a budget, and we say tips for the cleaner on the side.

So he walks over, turns his back to us so hiding the notes, rummages in his wallet and pulls out 4 notes, slips them together with our $20s and stacks them in a nice pile.

I thought it looked a bit sneaky, and knowing he was a tightwad I go over and he has left 4 sexy ass $1 bills. NICE.

I should add that he had approx $1500 in his wallet."

Thanks a million!