I finally decided to try to sell my custom built track loader. Here is the link if anyone is interested:
https://washingtondc.craigslist.org/nva/hvo/d/sterling-custom-built-compact-tracked/7486314509.html

I decided to ask for $15000 which might cover my costs except labor. It’s hard to guess what a machine that has no brand is worth so we’ll see how it goes.