I don't like to think about the costs but I'll see if I can help some.
A lot of what you'll need will depend heavily on the type of property you end up with. Mine is pretty hilly, mostly wooded. I have zero agricultural use for a tractor other than tilling up the small veggie garden we try to keep. My property is mostly "park-like" so I bought a sub-compact utility tractor (SCUT) which can handle a 5' finish mower, 4' box grader, 4' loader bucket, or a 4' rotary cutter (rough mower). Anything bigger than those and I'll need something with more HP. You can price out tractors on most manufacturer's websites pretty easily. You can always find used stuff too if you're comfortable with that. I'm no expert on engines and equipment so I'm usually more comfortable buying new, getting the 0% interest rate, getting the warranty, and learning to take care of stuff myself.
I mowed with that SCUT for 3 years, and it was slow as can be. We recently added a zero-turn mower to the collection and I couldn't be happier. It will literally cut my mowing time almost in half. I didn't believe the sales person and was going to be happy if it shaved 25% off but after a couple weeks I can confirm that it's almost twice as fast as using the SCUT. That said, you really won't want to buy a typical residential ZT (think HD/Lowes type) and should go with one of the commercial ones. I'd expect to pay $7-12k for a good brand depending on engine and cut size. (Scag, Exmark, Kubota, Deere, etc.) Again, deals can be found on used ones and spring is usually a good time as lawn care companies get new equipment and sell off the old.
My brother in law bought a side by side (Polaris Ranger 400) that he leaves on the property. It can haul about 500 lbs. in the dump bed or it can tow 1000 lbs. or so. It has come in very handy for hauling tools into the deeper parts of the woods on our property.
Other than those big items...
Power tools: Chain saws, chipper, string trimmers, portable generator.
Hand tools: Shovels, machetes, axes, pruning saws, pole saw, loppers, etc.
Misc: Gas cans, ropes/slings, gloves (lots of gloves), safety gear (glasses, ear muffs/plugs, etc.)
EDIT: and a truck and trailer for hauling any of the big equipment to the dealer/service guy whenever it inevitably breaks down. Most places seem to charge 50-100 bucks for pickup and delivery when you need service.
