My great-grandparents owned a farm in Indiana - my dad was the help during the summer and said it was extremely hard work. If something broke down YOU fixed it b/c you didn’t have money for a repairman and you needed that broken piece of machinery pronto, it couldn’t lay idle for too long.
Dad went on to earn a degree in physics and engineering at Purdue University and graduate degrees in physics later - says it all started by having to figure out how to repair small and large motors and farm equipment.
Many farmers continue to do their own repairs. Some of them have even built mighty fine tractors, including very large tractors. Large numbers of them collaborate with discussion boards on the Net. The costs are high. Planned obsolescence and built in fragility are among the highest costs.
Another cost: licensed tractor software that legally forbids farmers from doing repairs, threats to sue and all.