I recently bought a car and put $10,000 down on my credit card. I would have put the full $30,000 cost of the car on my Discover card but the dealership limited me to $10,000 because they said that they have to pay 2-3% in transcation fees to the credit card company and obviously this would put them out ~$750 on a $30,000 charge. Oh well, I was happy enough anyway to charge $10,000 on my Discover to get my $100 Cash Back Reward. What made me feel even better is knowing that the car dealership had to pay $250 in transaction fees so that I could get that $100 cash back. Yep, I think car salesmen are a bunch of crooks and knowing I was screwing them out of their $250 MADE MY DAY after all the crap I had to go through buying a car from them!