I built a front end loader for my little Yanmar 15hp tractor from
Cadplans, and I am quite happy with it- probably cost me a grand to buy
all the parts brand new, as opposed to a minimum of $3500 for a store
bought loader. The engineering is done right, the parts are well
thought out, and the thing works, as long as you are realistic about
what it will do. I think the backhoe plans from Cadplans are probably
similar. No way will it do the work of a real industrial machine, but
if you work within its limitations, for little jobs around the home
front, it will probably be fine.