Think of shopping for a bike this way...
"When you are still shopping, you're the boss. After you buy it, they (the seller) are the boss"
"People respect what you inspect--not what you expect"
With this above in mind, before buying the bike, inspect the following:
1) Have the stator and regulator/rectifier checked, to see if they are still performing within factory specs.
2) Have the (rear) driveshaft splines inspected, and lubed as necessary (if splines are dry, or nearly so).
3) Have the bike's battery load-tested, to make sure it's in good shape, too.
If it isn't, have them replace it with a sealed (AGM) battery.
4) Test ride the bike, if at all possible. Make sure it starts and idles well from a completely "cold" start; also, make sure it accelerates smoothy at speed. See if you can set the choke, and if the choke lever stays wherever you leave it (it should). If it can't start, idle and run smoothly from cold, you may have major carb work ahead.
5) Inspect the bike's frame beneath the battery box (it's under the bike's seat). If you see where rust has already started on the bike's frame underneath the battery area, walk away from the bike and the deal.
6) Check the tires for adequate pressure (especially b4 a test ride), and also check them for sidewall cracking and signs of dry rotting. The original tires on my '05 were Bridgestone Exedras, I believe. If the tires are more than 6 years old via the date code on the tire sidewalls, have them replaced.
If they give you a hard time about any of the above, simply remind them that the bike isn't being sold with a warranty. Thus, you are just doing buyer "due diligence". If they still give you strange looks or bad body language or other, simply take your business elsewhere. There are plenty of VN750s out there; if you are serious about one, finding another isn't really hard.
If in good shape and proper tune, this bike is extemely
smooth from idle all the way to redline. I have over 20k on my '05--and I wouldn't have kept it for 5 years if it wasn't a smooth, fun ride....
Good luck with your bike search....let us know how it goes....(i.e., the bike, and the search......