I know many a carpenter will not install someone else's stuff. It is a bit of an attitude, and to be honest I had the same attitude many years ago. It sounds a bit like this: "Well, if they like their stuff so much let them install it" or if bought at a box store like Home Depot or Lowes, "Why should I put that in, I could have made something so much better".
This is a wrong attitude!!!. As a Christian guy, I understand that I am led into many different situations and opportunities to influence or do something for someone. Either for my benefit, their benefit, but usually both.
So I got a call to stain and install a mantle purchased at one of the box stores, but the people were on a budget. While in the home I realized they needed a temporary ramp in the home (the wife was recovering from a stroke) I think they were forgoeing the ramp because it would be temporary and did not want that expense. Well when I took the mantle to the shop to stain, I just built the ramp anyway and decided to give it to them. They were extremely pleased and insisted on paying for the materials.
They also gave me a short list of other things they need done in the coming weeks/months. You see even the small jobs can always turn into something bigger. But most importantly, lets all try and do right by people we come across - it is not a hard thing to just be a nice guy.