What to look for then ?

Personally when I go to buy a bike I can make a decision pretty quickly before looking at the bike just by speaking to the owner.
If buying blind from a poorly written ebay advert all written in txt speak with little real valid information, then expect the owner to be perhaps young, and as such be prepared to see a bike that’s actually quite typical now at the lower end of the price spectrum.
However an owner who has owned the bike for a number of years, presents you with some bills and tells you all about the works he has done to it over the years gives a feeling of confidence when buying.
Common sense will tell you to run away fast, or try and secure a nice bike.
I would never be bothered about a service history, you buy taking a chance, a well serviced and maintained bike could always throw a rod out of the block tomorrow, and always buy after factoring in a full service by default, and a strip and clean to get intimate with the bikes workings, and spot any bodges or anything about to drop off.

The difference in the quality of bikes is quite extreme,
is the bike clean ?
chain oiled ? or hanging off ?
sprockets in good order or looking like lethal throwing stars ?
Tyres in good condition and a good brand or replaced with cheap avon death masters or swallow hedge finders?
Is the bodykit original ? or has it been replaced with a Chinese bodykit ?
Much aftermarket stuff fitted ?
if it’s got an aftermarket can attached has it been re-jetted to suit and more importantly jetted correctly?
Bikes with original paint and panels (be careful to check the paint is genuine (genuine is mainly stickers on top of paint and as such has a rough edge) are often worth a lot more than bikes with a paintjob on some aftermarket panels. However if your after a track bike the above is irrelevant.
It will always be harder to sell on a bike with your custom paintjob than a standard one so think before you go ripping all the original parts off and chucking them away. Halving your target audience when bored of the bike may see you regretting making all those changes when you get no one expressing any interest in your bike when it’s for sale.

So which do I buy ? NC30 or NC35 ?

All down to personal preference of course. A few of us have owned a few of both over the years and often the NC30 is seen as the classic bike and one most prefer for one reason or another. However there is no denying the RVF is a pretty looking bike which still looks modern today which will appeal to the younger buyer. The NC30 has the classic looks and esp in the early Red white and blue colours (same as the majority of UK spec bikes based on the RC30 scheme) is the one most NC30 buyers seem to want.
There are small differences between the bikes which I will try and sum up quickly.
The NC30 feels slightly thinner and taller, seems to fit together better, seems a bit more soild, and pulls very well up top with fine solid handling. However has a very tall first gear which some don’t like. It also has an 18” rear wheel which means finding track rubber can be harder. But the 30 has classic lines and looks.
The NC35 feels a tad lower and easier to handle. It has a stronger feeling mid range but can be at the expense of top end (not in all cases, every bike is different, but often), brakes are excellent, but shock and forks are poor quality even although USD. Some 35 plastics are still available new from david silver spares however are very costly.

Summary

The NC30/35 is a well built bike. Its testament to Honda’s build quality that they are still going today even after suffering years of use and abuse at the hand of often skint owners dipping their toe into “first bike bike” ownership. But at best even the newest NC35 is still 14 years old now so as with any bike – buy and budget accordingly. With all the owners on the Forums you are not far from good solid tried and tested advice. Thanks for taking the time to read this I hope it aids in your purchase.