If you're not in a club then you're probably not an insured caver, which is likely to be more of an issue.
Thats a good point. As is the related issue of your age - if you're under 18, access is also likely to be an issue to some caves, no matter how bona fide you are.
Where lies the boundary betwen a 'novice' and a 'bona fide' caver? Some notable caves have access conditions that state 'no novices'. Tricky thing definitions... No, I'm not trolling - this is a genuine point. University clubs are far from unknown to take parties of what I'd term novices down such caves, with a, say, 1:6 leader ratio (I plead guilty to doing the same meself 25+ years ago) yet with a 1:1 or 2[leaders]:1 [under-18] ratio, I cannot take my son. Funny old world.
The only UK legal definition (maybe not the most useful admittedly) of bona fide that I iknow of, is the old one of pubs being permitted to serve bona fide travellers in the era of Sunday closing. If I recall correctly, it required the drinker to have travelled at least 3 miles. Seems a pritty low threshold - which suggests that having done a couple of caving trips converts a novice or non-caver into a bona fide caver.