Need Some Input

Ok well I bit the bullet. Called down south and drove an hour to see a 1996 Dodge Durango with 135K on the clock. Coolant looked good, oil looked clean, had to jerry rig the ignition but she fired up and sounded good. No knocking, no belt squeal, no white smoke. Engine was cold when we started it so I let it run tell it hit running temp and revved the engine to see if there was any noises. Nothing, all in all the motor seemed to be running well. Oil pressure and temp gauge were within normal operating ranges, Pulled Valve covers and it looked fairly clean. Paid 648 bucks for it. Guy is going to pull it tomorrow. People are funny guy asks me if I want a receipt I say yes I would. Guy says oh well then I will have to charge you taxes gonna be another 48 bucks you sure you want it if you don't take a receipt I will only charge 600. I said so let me get this straight you want me to hand you cash and I am supposed to just thank you and walk away with nothing? I said here is the 48 bucks I would like a receipt. He must have thought I had a tattoo on my forehead saying dumb ***.