Seriously? This is the exact thing that ruins cookouts! Tbh that "trust building" side is how you end up with one friend asking you to re-tile their entire bathroom for "exposure". Alexlewis is totally right, that feeling used part creeps up on you fast. It stops being help and starts being expected free labor, and then you just get quiet and mad about it. Setting a clear line from the start saves the friendship way more than unlimited free work ever could.