Opinions please

I k now my opinion is worthless around here but....an agreement is an agreement. Pretty simple. He agreed to give it to you as payment. He wants it back, no discounted rate, either monetary or hour wise. Would also tack on a few hours for the time it was sitting with the crap in the cylinders. Would also tack on a minimum of an hour for the time you no doubt spent cleaning all the rust and s hit off the floor of your shop.