If it were me and from the information you provided, this is what I would do:
1. Rent a very large machine to do the major work. You can make short work of some tall tasks with a ~90hp backhoe for example. Very surprising how much work you can get done in just a weekend with one if you plan ahead (have a plan, already have dirt/gravel delivered, trees already cut, etc)
2. Buy a much smaller ~25ish HP machine for maintenance. Assuming you don't need to move huge round bales or deal with some other real heavy application ongoing, it is surprising what a little tractor like mine can do. I can move dirt/gravel, grade, maintain a gravel road, mow/bush hog, till, fix erosion problems, etc. I can't do stuff like dig out a massive tree stump or quickly move, spread, and level a triaxle load of gravel (can do it, just a small scoop at a time vs a cu yd+ at a time).
I have cut and cleared some nasty stuff with my smallish tractor & 5' bush hog. Moved, spread, leveled/formed 2-3 loads each of crushed concrete & fill dirt. My only implements are the 5' bush hog, small ballast box, loader bucket, pallet forks, and 5' box blade. With just that little bit of stuff there is a lot I can do. Do I wish I could lift a little more weight, have an 8' dump clearance, or carry more in the bucket? Absolutely. But for me it was the difference of just write a check for it or pay at least 2x as much and make payments for the bigger machine. Works out SO much cheaper owning and maintaining the little tractor vs a larger one and then just occasionally renting a backhoe for a weekend when there is something major that needs done that my little tractor is either incapable or too slow to get done.
I would also make HST a high priority on a small piece of land like that. Mine is only 6AC and I like how tight my machine turns and the ease of direction changes since I do lots of FEL work. Also incredibly easy for my wife to just jump on it and do stuff too. Small so easy to get on and off, and the controls are all very intuitive so it isn't intimidating for her to just hop and and do something.
I understand where "figure out how much tractor you need and then buy one size bigger" comes from. But I'm not real sure that applies the same to folks like us since the difference between 5AC and 50AC is significant. For a small area, use a small tractor. Rent a big toy occasionally to cover that very small % of the time brute force is required.