First of all, does it start right up? If not,
it's only going to be worse once you get it home, especially after the
weather turns colder. An engine can be in pretty poor condition and
still start easily in warm weather, likewise, just because it doesn't
start easily doesn't mean that it's worn out, but if you have any reason
to believe the seller is has more mechanical capabilities than yourself,
hard starting should be viewed with suspicion. There are always lots
of tractors on the market. For our purposes here, if getting the
engine started in the first place requires any special skills or
procedures, just move on to the next one.
Assuming it turns over quickly and fires right up, does
it idle smoothly and is there any excessive smoking from the exhaust?
Again, either condition is not a sure sign of trouble, but
since we're not mechanics, maybe we'll want to pass on anything that looks
questionable.
Also, don't forget to look for are oil leaks, which can
come from simply not having a bolt tightened enough or something more
sinister like main bearings about to fail. If the tractor has been
recently cleaned or repainted, this might be harder to determine, so
leaving it to idle for a while might not be a bad idea.

Generally speaking, you can't expect to pay a really
low price and not have a few things wrong with the tractor, but like many
things, if you'll investigate four or five in your price range, you'll
probably see one that stands above the rest.
The best way to assure that you've
found at least a fair deal is to be familiar with the market and that's a
lot easier than it used to be. Once you've decided on the make and model
you want to buy, I recommend you spend a few hours looking over the
selection at
TractorHouse.com. You'll find several examples of most any popular
model you want to consider, and you can compare the prices and conditions
there until you're a near-expert. You may even find the tractor you're
looking for within a reasonable distance of your home.
You can also find a selection of
used attachments there.
Things may be different in your
area, but In my neck of the woods, where the vegetation is lush and the
rains are frequent, most everyone who buys a small tractor usually also
purchases a brush-cutter of some kind, and a grading blade of some kind.
I'd like to say a word about these.
First, the brush-cutter, what's
generically called a bush-hog. For $500-or $600 you can get a new
brush-cutter made with a sheet metal body. Don't buy one of these unless
all you really want is to mow grass (in which case you're better off with
a finish mower). Real bush-hogging requires something with heavy
steel plate, like the brand-name Bush-hog cutters, if you're looking for
equipment that will last more than a season or two. These cost more in
the neighborhood of $1500 and up new, but since they'll last for decades,
you're better off buying a used one than a new model of the lighter
version.
As for grading blades, a straight
blade does a poor job of most of the things you want to do with a blade.
If you want to smooth your driveway, a box-blade is much, much more
effective. Even a rock-rake does a better job of smoothing roads than a
straight blade (although the straight blade will do a barely-adequate job
if you turn it around backwards).