I have a potential buyer on Craigslist for a lens I am selling who is buying it for a high school and needs an invoice to be reimbursed. He says he would rather not do PayPal and prefers to do a cash transaction. I do not have a business to issue invoices, and was wondering if there is something I can do here that I am not aware of. Any help will be very helpful, thanks!
Simply give him a letter, in standard 'classical letter' format, with your and his name, address and etc. The letter could say something like "Invoice for 'name of lens', for a cost of $'dollars', payment in full required at time of sale', 'thanks and etc' , 'yours truly'.
Then, when you get the money, write on the letter (in white space at the bottom), "Paid in full, 'date', 'your signature'. You're done!
Oh by the way I have sold many items on CL and only a few times has anyone asked for a written receipt I have no issues about this whatsoever. It also makes it a little safer for the buyer imo