I tell you what, sometimes some of you all that have a garage or shop full of parts, mowers, and other junk make me jealous! I've been having to scavenge flea markets, yard sales, and web sites for all my parts.
I will add an idea that has worked for me though if you are trying to build a machine on a budget but might be in my boat, which is renting a place to live with limited resources at hand ( junk piles). I've been finding junker lawn mowers, weed eaters, blowers, and other power equipment, fixing it up, and reselling it. I can get as much as $75 for a nice push mower that's been gone through. I've sold 6 mowers so far this year, and that's just about covered my costs so far. Just an idea.