Here's pretty much what I posted on another thread recently to a similar question - IMO: "nothing costs like a dozer can...." -
There's a lot of "cheap" dozers around & very few represent good value, add to that small dozers invariably cop more than their fair share of abuse being pushed into tasks usually well above their "weight" & the cost can soon escalate.
Also consider relative to their "output" it costs roughly the same to repair, maintain or replace undercarriage on anything up to c.D6/7 sized machines & for the uninitiated dozer ownership can quickly become a whole world of mega $'s & pain when the first major repair comes your way - make no mistake owner any dozer is a high cost exercise. We run earthmoving gear including dozers & traxcavators on our farms/commercial earthmoving operation & if there was anyway I could avoid dozer/traxcavator ownership I would, unfortunately for us it doesn't (just) make overall commerical sense.
Depending on what you're trying to achieve, c.200acres is a large job of making good a logging "mess", I'd suggest you may be far better off with an excavator in the c.12T (maybe up to say 20T) class: it'll dig up stumps quicker & far cheaper than small dozers & is a whole lot cheaper to run on a cost/hr basis, fit the excavator with a thumb or grab & you can stack a burn pile really easily (& move fairly large rocks around), with the added bonus is an excavator isn't going to tear your land up like a dozer & has much greater versatility - you'll also find reselling any excavator is generally easier than a fairly limited market for a small dozer.
Also running a dozer for the uninitiated might be fun for the first day but it's also a whole lot harder to master & whole a lot rougher on the operator than an excavator, & whilst bogging a dozer is quite easy, getting it "unstuck" is a major exercise, whereas unless you've tried to "walk on water" an excavator can usually self recover.
Operating a small & aged dozer within its design capability will work out close to 3hoours working to 1hours repairs/amaintenance (at best, start asking much more of an already aged machine & the costs/downtime are going to escalate quickly & exponentially - for c200 acres pop the stumps/stack with an excavator then if you want to cultivate the land use a contractor with a large dozer (min.D7) fitted with root rake (or better stiill contract out the whole job)