I think it is fair game, keeps sellers on their toes and and all that 😆
There are a few odd ones in the classifieds that I never understand.
My part is broken but “only needs a XXX” and it will be as good as new. I will therefore sell it to you for 50% of the RRP.
I have half a well used gear cable, its a bit tatty but will do for somebody. 5p and it is yours if you cover the postage or happen to be in Redditch on a bank holiday Tuesday between 3:00 and 3:02.
I may, possibly, perhaps, potentially sell my bike but I am not sure so I wont put any photos, the spec or the size and will see who wants to buy it.
And my personal favourite, I have a YYY for sale, £10. 6 replies to say they will take it but the seller then goes offline for 5 weeks before relisting it 3 months later.
😀