Easy 600$$$$$
My grandpas friends from way back when said his computer was running very slow and asked if I could fix it. I said I would give it a shot. I went to his place and looked at the computer. It was an old Dell 410 desktop. I asked how old it was and he said it was around 5-6 years old. I opened it up and it was just dust. Everything on the inside was coated in more than an inch of dust. He had his desktop laying on its side by the way, so that's how all the dust stacked up. I dusted it with an air duster and it worked fine, it wasn't shutting down randomly anymore. He was so impressed at what little work I had done that he gave me 600$ and asked more my number in case he needed help with other technology problems. I later learned that this guy was the CEO of an off shore drilling company that I will not name, and after I learned that I didn't feel so bad about taking the 600$.
TL;DR
Help old people because they have a fuck ton of money.