I don't know if it still works, but there used to be some trick you could use whereby if you have no money at all the bandits robbing you would make you a multi-billionaire by giving you vast amounts instead.
A preoccupation with the next world is a clear indication of an inability to cope credibly with this one.
When you get to that part go to the 2nd floor of the flea market and there should be a box up there you can put your stuff in. Put it in then spend as much as you can on supplies with the traders there. There is no way to get the money back but why not spend it on something good before you get mugged?
What's your problem? We're just sitting here, taking a little break. It's nice and quiet, no one around....
If you have an earlier save before you got mugged, you can instead spend
it on weapon and armor upgrades, buy ammo, buy armors and other stuff
and have as little or none of it left when it is time to go get your mugging.