I've never been charged a lot but I have been refused reimbursement for a dev site before.  I was trying to make a point that a Server couldn't handle the load and was set up incorrectly and cheap cloud hosting would perform better.  So I stayed an apps and database with my own credit card.  I was right but was not reimbursed.  The company spent a lot of money on new hardware and I left the company.  I didn't accept that my code was to blame. Seeing that the money spent on my skills was more expensive than hardware and all it needed better hosting not some miracle coding technique. So me leaving freed up even more budget, until of course they needed to replace me with 3 or 4 devs.  I still haven't seen that expense check.