The earlier series were the worst (or perhaps they just got better at deceiving?) - you'd see whatever car that week with brand new chromed rostyles, with thick red rusted wheel nuts. Take a careful look at the 'before' and there'd be a just-noticeable bleb of rust on the bottom of a panel. At the end of the prog that rust was still there, just [almost] hidden by clever camera angles. Now on the show stuff like this just miraculously disappears, as said, without being factored into the cost.
Seem to recall a Suzuki SJ which they got cheap (so it
must be good
) and after a small fortune spent on various chrome plating things, right near the end of the prog it fails the MoT because 'oh hand on, the body and chassis are rusted beyond any feasible or even physically possible repair' so the car was only fit for use off public roads/scrap.
I enjoy bits of it - but have started to mute it when Mike is on. (which is luckily only the first and last 5 mins, where he traditionally drives like a monkey covered in termites that has been trained to repeat the phrase 'sorite, innit? mate! mate! oi can't believe what Ed 'as dan.'