We had our plumber come and install a new toilet and a new shower back in October/November. He and his guys have done work at our house in the past, he's a good dude who does good work. The catch is, he's really bad about billing... 

I've reached out twice saying that the job is done (there was a drywall guy working after he wrapped up), and everything looked great, and to send me the invoice when he can. I'm happy to pay him. 

He hasn't sent it yet, and it's been about three months. My wife says the ball is in his court since we've called a couple times and as a businessman it's his responsibility to invoice us. But I'm starting to feel like I'm taking advantage of him... 

Am I the asshole for not pursuing to pay him? On one hand, free plumber work. On the other hand, this is probably a couple thousand bucks he's sitting on and I feel bad about that. 