OTG... here's my advice.. take it for what it costs..
1, the N series are neat and nostalgic, and you can spend nearly as much buying one and restoring it as you can buying a slightly later model and restoring it.. only difference.. you have more 'real' tractor in your hand if you buy a later one, once you are done with the job.
On the diesel 2000.. hard to say without seeing pics of it and know more. does it start easy? does it need ether to start? smoke? slobber?.. does it have the 4spd, or 6 or 8 or? tranny..
other details in general on an old tractor to think about are rubber, tinwork, genny or alternator? does it charge.. are you gonna change it out?
Me? I'd AT LEAST look for a 55+ machine IE.. a 6XX/8XX/7XX/9XX/5XX or the early 4 cyl 2000/4000. If looking 53-64, get a gasser.. if 65+.. get a diesel.
post back some more info on that 2000
going and checking out an old tractor is more of an art than a science.
also.. as FWJ hinted.. it's easy to 'double' the cost of a refurb.. ie.. buy the machine, and even if it runs ok, it's easy to sink the purchase price back into it again making ir run great and look pretty.
if it's an ugly beater that runs bad.. you can sink 2x to 3x the price into it making it look and run good.
on the 2000 3 cyl, for instance.. for 2500$ if the front hood nose clip is damaged beyond body work repair.. be ready to spend 500$ to get one delivered to your door, plus another 50$ for a grill screen.. fenders.. 150$ a pop.. etc. rubber, if rim is ok.. alot at least 250$ for each rear, and go ahead and say a round 100$ for the fronts, each.
economy paint is 35$ a gallon.. economy primer 35$/g, hardner, 14$/pint, supplies like mineral spirits and naptha are 5-10$ a jug.. etc.. then you need to add up all the surfacing supplies like sand paper, sanding sponges, 3m prep discs, bondo, glazing putty, plus a few rattle cans of primer for spot fixes, some fiberglass matting and resin for small repairs. etc. etc.
cleaning supplies.. figure on getting a gallon of soap based degreaser, and at least a couple cans of petro-degreaser.... plus you will likely need it pressure washed a couple times between scraping, degreaseing with petro, more scraping, then a final soap degreasing.. etc. masking materials like blue tape and paper.. etc.. etc.
add to that basic servicing supplies... the bat if needed is a 100+$ job.. cables and ends $$, oil for crankcase and rear end, even if using economy is gonna be about 100$ for a full service including greasings.
not disuading you.. just prepairing you.. the purchase price is only the front door to a project. and yeah.. buying one in decent looking and running condition, is generally a good step up on a first project. once you get a few under yer feet you can go for the rusted out hulks puleld out of the hedge rows that take you 2 months to even locate parts for it, then start taking apart all the broken pieces and drilling out bolts..
soundguy