Just you and me on here I think - shame, could be so much better with more participation.
Anyway, depending what the money is on the one you're looking at - if it's from a dealer/trade - once you get to a price you're happy with, you could always finish by trying 'throw the cam-belt change in and you've got a deal' - it costs them far less to get it done than it would for you (probably £3-400) so they might suck it up to get the sale. If they don't you tried, then you'd have to weigh it up.
I got mine in 2018 and the only 'service book' the previous owner had was one of the blank generic ones you can get which he was 'given when he bought it' the year before, the only 'stamp' at that time being a service and cambelt, and by the time I bought the car a second 'stamp' had been added approximately a year later, a few months before I bought it. So I have the warm glow that it 'should' have been changed in 2017 at approx 55K, but given that same service had spark plugs ticked too, on a car without them, it could all be cobblers and I ride by the seat of my pants.
Thing is, from your perspective, it might or might not be due yet (54K or 90K etc) and maybe you wouldn't get to 90K in the next 3 years, but it will also be 3 years older then so possibly an 8 year old belt. I really don't know what I would do.
Until recently my view was different - picked up a 2007 getz for my lad (top tip - dirt cheap to insure for new drivers and a great car if image doesn't bother you) - got it at local car auction - had over 150K miles and a pretty good main dealer stamped book, although the last cam-belt 'proven' was 5 years before. I thought, for a £300 car it's not worth doing, I've never had one go on any of my cars in over 30 years of driving, and I've driven some rubbish. I kept it well self serviced except that belt. Over 2 years later, after a gig and night in a London hotel pretty hung over, have a call from son who, having just left the south coast to take his girlfriend to Cadbury world on a short birthday break on her 21st, had snapped the belt. His few days were ruined, her birthday was, my leisurely morning was and I then had the aggro of getting it dragged somewhere closer than the AA would, trying to help him get another car or new engine (which muggins here would have to buy/collect/fit). Found cheap low miles engine, DID THE CAMBELT ON IT, fitted it in the cold and rain (from underneath as I didn't have a hoist and could only work on it as and when so didn't want to hire endlessly), to find main crankshaft seal knackered - strip down again, deep joy.
He's back on the road but I really am more nervous about my own now given the 'service book' I have. A whole world of aggro if it goes, unless you have the top levels of breakdown and warranty cover, which cost more than doing the belt.
I still kick myself on that getz - cambelt was a doddle in the end, wish I'd done it when I got the car but thought saving the £50 (plus my time) was worth it. It isn't easy on the NV though, still just shutting my mind to it when I drive 🙏