You used to be able to find the exact same polisher as the DAS6 V1, but sold under different brands, for around £50, not sure if that’s still an option? The Draper one looks like it’s the same polisher as the V2, but then it’s not that much cheaper and doesn’t come with the bag.
(the Vonhaus/Argos one that’s also available under various brands is more basic and, again, really not <that> much cheaper. I’d be pretty confident that there’s other good cheap options but you lose that confidence)
Thing is, the difference between a really cheap polisher and a budget one isn’t massive but what you gain largely is safety- you’re less likely to screw it up, less likely to have a pad fail badly or be badly specced, stuff like that. It doesn’t take a lot for a bargain to become a problem.
Equally, that depends a lot on the operator, if you’re careful you can get great results even with a cheap random orbit sander and an adaptor. I’ve done panels up to a high, if not quite pro standard that way but it’s harder and tbh I’m not sure I’d want to do it on a car (different rules when it’s something you painted yourself!)