Bill your recent “to sell or not” thread covered a lot if this when you were looking to buy at £6k. At £2.5k you are nowadays potentially in banger territory and 10 plus years old. In general terms avoid diesels, chain cam VAG, automatics and cars that were expensive new. Look for simple, Japanese or basic common cars like Ford or Vauxhall. As you have already found you will get opinions either way even on these broad guidelines.
It might be best not to get too hung up on particular models but the only one if your short list I would consider is a Focus. I’d also look at Hondas including the Tardis like Jazz. But I’d be looking generally to see what’s around locally on Gumtree and Autotrader and filtering out those worth looking at on condition and how you assess the seller. The ideal car is probably one that’s being sold privately and been owned by the seller for several years and where there seems to be a good reason for sale. Someone selling an old well cared for car on giving up driving for example. Or if you know the seller personally.
Overall, at this end of the market, you will find a lot of dross and it will be hard to find anything half decent. Good cars do exist but will be rare.