I am perhaps in a similar situation but im 35 with only 20 acres. Moved from the city about one year ago and didn't know anything about chainsaws and tractors etc. The old owner left behind a bunch of old saws and welders/tools so we figured what the heck let's jump in with both feet and go all in on rural life. Rather than hiring out we opted to buy an old 1976 track loader with backhoe and even though I am slow and inefficient, and I spend way too much time researching how to fix things , and then working my way through it, I'd have to say it was the correct path for us, and would recommend something similar as I've learned a ton and gained a lot of confidence. The best part is that all of the depreciation has pretty much taken place, so when all the heavy stuff is done, selling it for what we paid is a very likely outcome. Only cost would be gas and parts. It definitely tears up the soil, but that heals quick. All my older friends tell me it's about the journey, so I'm trying to keep that perspective. Cheers, 100 acres would be awesome!