Neat game, shooting weaponised money felt pretty good.
Normally I'd suggest being able to hold down the fire button, but in this case where bullets are money and is not plentiful, it makes sense not to.
I found myself quite low on cash at all times despite trying to conserve ammo. It could be nice to have an influx of money come from destroying a portal.
The lighting on bullets was a very nice touch that did quite a bit for the aesthetic.
All in all, nice job :D