Even when we had corporate cards, you had to fill out an expense report, everything has to have a receipt except for meals under $25. You have to print your expense report on green paper and tape your receipts to white paper. Then have your boss sign it before sending it to accounting. Then pray you didn't make a simple mistake, which would mean you eventually get it back to be corrected because the $8.34 charge was actually $8.43. BTW, in addition to my my X-mas purchases getting cancelled, my rental car didn't get reserved for my trip to Houston yesterday. Fortunately they had cars available, but I was unable to get the normal rate.
I guess doing it this way works from the companies end - they only refund you what you ask for, and what is appropriate, not they pay for everything and have to claim back inappropriate spending... I would probably look to a second credit card so that you have your normal one to use for personal spending, and a second company one for business - you can keep them separate which means you shouldn't have any problems hitting the limit, and can keep some distance between personal and work. This does assume that you have a good enough rating to get said cards, and have enough of a float in your bank to cover the company card should there be a problem. If you can't afford to do it this way, time to stop travelling for work I guess...