My thoughts on value:
I'm looking at buying a 2001 NH TC35 12x12 shuttle with 16LA loader - 6500-8500. Might get a tad more, but I think in a private seller sale thats close to what most would expect. Just something about this description that scares me - less hours and no "rebuild" you might be at 10k - lots of sellers asking the moon for things does not make things more valuable. Again, rebuild should not have been needed at this point, and who did the rebuild?
disc - $300-500
"nearly new 4' brushhog" - 750, new you can buy low end 4 footers for 1-1100, personally a small unit for a tractor of that size in my opinion. A more popular 5 or 6' model is not much more used - and would work well. Lots of SCUT out there that need a 4' - this is not one of them.
Box Blade - $500
So by my math - pieced out, you have a 10k bundle of goodies here. Buyer frenzy in an auction - you might see 12,500 total - but private seller and all or nothing, 12,500 is high.
Another way to think of this is "what do you need" - First figure the cost of a new unit that meets your needs - then price out comparable units used that meet your needs. The way I would view "comparable" units is Tier A. Deere/Kubota - Tier B. New Holland/Massey/Case and just below those Mahindra/LS/Kioti - PLEASE NOTE THIS IS NOT AN OPINION ON QUALITY - just an opinion on resale only! Lets be honest, a Deere is easier to resell used than a LS of equal size at the same price. I put a 30hp Deere out and a 30hp LS out with the same price - the Deere sells first - does not mean it will be a better unit, just easier to sell at a price point.
IF the NH is 50% of the price of a new unit that meets your needs - or 70% of a more recent used unit with under 1500 hours - I would say that is your "break even" point of savings. You can anticipate higher upkeep cost with more hours, but being honest - upkeep is a complete and total gamble. You can go years on a unit like this without needing anything - or you could hit a 4 figure repair days in. The only "known" is that it is more probable you would hit the big repair bill on a 2001 with 3500 hours than you likely would on a 2011 with 1100 hours for example.
IF you need the power for a unit of that size, its not a horrible deal - but a tad high. If your just looking for a tractor to fit your budget and thinking "bigger is better" - but could get by on a smaller sized unit - there are much better buys out there in the market if you shop around. Even in higher priced markets, shipping rates from cheaper markets are your best bet.