Also when you're low on funds check your insurance!
If you can't afford the rebuy you lose the lot and you're back in a stock sidewinder.
I'm kind of surprised there isn't some kind of warning on this. OK, planet landings and take off it would be different, but maybe when launching from a space station there could be a message delivered saying 'Warning CMDR, your insurance premium has not been paid, please add sufficient funds to your account' or words to this effect.