There’s never been a better time to buy an instrument on a budget, the build quality of the £150 instruments these days is as good as the £500 instruments from a couple decades ago.
Personally I’d go with a secondhand Yamaha, I don’t think you will get better value than those. I paid not much more than your budget for my BB435 and it holds its own with my custom basses. After a year or so, you’ll probably figure out exactly what you want and then you can upgrade if you wish, and won’t lose any money on resale.