I have been building machines and selling plans for 5 years. The plan sets that I sell are drawn from a finished machine that has been tested and improved. Both machines can be built without expensive specialty tools.
The Backhoe will take about 45 hours to build, materials will cost approximately, $1500.00.
The Electric Walk Behind Tractor will take about 50 hours to build, materials will cost approximately, $950.00 plus batteries.
The build time will depend on the builders experience. materials cost is based on all new parts. Cost of materials will vary.