What about the earlier versions?

Hello everyone,
I’ve been looking for a second-hand Brompton for a while now, but it hasn’t been easy to find a good deal in my area. This one has been listed for quite some time. The current seller is already the second owner and says the bike should be around 20 years old (+/–). However, I suspect it’s older because of the Sturmey Archer shifters. The asking price is about €700. Do you think that’s a fair price?

What are your thoughts on the older models in general? I know a lot has changed with Bromptons in recent years, but how does that affect the riding and folding experience? I’m mainly looking for a bike that rides reasonably well and can easily be taken on trains, but unfortunately my budget is capped at €700. Maybe I should just wait for better deals? Not sure…..