I agree, take the money and do him a favor. It is in his best interest. He may want to use you regularly and understands you won't do it for free/cheap forever.
I called a young dairyman 10 miles from here and he said he'd AI my couple of cows for $20 bucks a trip for one cow. While that sounded great for me, I figured he would eventually lose interest for that $, like when he was in the middle of haying or milking or whatever. So I pay him $50 and will probably bump that up to keep him coming. He's still cheaper than the guy who advertises his services.
Not to mention many of us have experienced the freeloaders who take advantage of others - your neighbor probably doesn't want to be counted among them.
