Used tractors are an interesting purchase. I recommend everyone have one unless you live in an apartment. If you shop around and buy something a few years old at a reasonable price, i my experience this will happen:
Build a dry storage location for a tractor. You buy the tractor for say $15,000. You use it to work around you place while taking good care of it. Once you finish your projects, you put it back on the market and recover your original costs. Yes the tractor will take a hit for maybe putting say 1000 hours on it. You sell the tractor for $12,000. The cost of operation becomes depreciation, fuel and maintenance. The storage building you can continue to use so no loss there. The money you saved on physician expenses and ibuprofen can be written off the purchase price as you no longer need to dig stuff up by hand. This may bring the total cost of ownership down as well. Now you are looking at a loss of $4,000 for 1000 hours of work or $4/hour to get at least 10 times the amount of work accomplished as a shovel, rake and wheelbarrow would most have provided you.
PLUS! you own a tractor. BTW, do not buy a trailer as they lead to loaning and add to your cost of ownership..... Just take care of it and it will hold it's value well.