Am I undercharging?

i'd say 175 per car is decent. but i would charge $200 mostly coz of the PP that you are thinking. you said you would do HDR and stuff.

im sure, your friend is looking for more than just snapshots, pun not intended, thats why he is paying decent money for it. but if he is really a good friend, 175 would be good per car.

but just remember, get it all down on a written agreement just in case. if he is a real friend, one that wont screw you over in the future, then he would agree to sign a contract. he should not be against it, coz he did say, he would only pay per car so its a win-win situation for the both of you.

best of luck for you and your friend!

This has been repeated by several people, and it's important. The guy may be a friend, but he is in business to make money--it's better that both parties have a fully businesslike attitude. When one person has a business attitude about a matter and the other does not is when misunderstandings occur.