A troll is a post that is sent out just to get a reaction.
Used twice, sold for £90 and has a seatbelt? Something doesn't sound right. You can't buy seatbelts you have to design and fit them yourself, or talk a mate into doing it for you. Anyone who is prepared to go to this length would probably :
a) not buy a buggy thay are only going to use twice
b) knows how and where to get more than £90 for a new flexi.
I guess I'm just overly suspicious, in which case you really have hit lucky.
I wouldn't remove the footstraps, by the way. I think they are useful right from the start. If you hit a bump and one foot slips off, then having footstraps can mean that you keep control of the steering long enough to get your foot back in. Your choice though, as getting yanked out of the bug with a foot still caught is potentially dangerous.
Loki