I usually didn't sell parts either unless I knew that I'd never use them and also do my own building projects. Heck, my dad and I built my 1500 sq ft shop back in 84. He was 63 at the time and well, didn't appreciated the fact he was getting up on top of the thing to get the ridge and rafters started and then got down and do all the cutting. I'm 10 years past 63 and don't even want to get up on a finished roof let alone one that is still sticks. At one time I could walk the frame of a house without any problem and was dang good at it. Nowadays, I'm doing good to walk half way steady just getting out of bed to go to the bathroom at 2am!
