Traditionally, poor spelling and a weak grasp of written English was the preserve of the terminally shady, but it’s now seemingly a universal right. Some folks just don’t put an ounce of effort in their adverts. I’d guess this is an example of that.
So is he selling lots of the same bike of different sizes? And you can pick up a sim card from Tesco for 99p to seem more legit,who knows it might very well be a bargain to be had,just open up a paypal dispute at the same time as you send your cash :-).