<prompt> Human: I was recently commissioned to build a piece of machinery by a personal friend. Before I started, neither one of us discussed compensation for my time, only prices of parts. When I was finished, he brought up the topic of paying me. The standard rate in this entire industry for this work is 250, so thats what I asked for. He agreed to pay me that amount by Venmo, and then said to keep the 76 left in the budget on top of that. We agreed, he left with his object, and I sent a request on Venmo for 250. He declined it and paid me 300, then texted me Hey I declined your request for 250. I just paid you 300 instead. Thanks appreciate it! So I was paid 376 dollars for a 250 service, and I dont feel like I should accept it. It doesnt feel right. Should I send 50 back? Ive never dealt with a situation like this before.  <response>: Ive intentionally overpaid vendors that do quality work and undervalue themselves.I had a guy do a couple hundred square feet of tile. Id gotten bids elsewhere, and his came in at half of theirs. This was not in a critical area, so I had him do it, assuming he would just tile and grout. He wanted something for his portfolio, so he offered to do a more complex design tiles at 45s rather than 90s, used epoxy rather than thinset, grouted, and also treated the tiles when done granite tiles. His work was precise, kicked ass, and he did it on a weekend to boot. It was clear he was trying to break into the industry, so I told him to take as many pictures as he wanted for his portfolio and gave him a 50 tip.Lots of people will do this to ensure that, when your good work is recognized, those people still get priority. Think of it as a retainer for a future job. 