Anyway, let's get back on topic.
Disclaimer first: all of my knowledge on turntables was gleaned from subjectivists and my own personal experience. I do not have any measurements or know of any publications to back any of this up!
Re: turntables, there are many philosophies on the market. Belt drive vs. direct drive vs. "exotic" drive types (e.g. the new Esoteric turntable). Many different types of bearings, including exotic types like air suspension or magnetic suspension. Also many different types of platters - some believe in high mass / high inertia, some in low mass / low inertia. But, if we are talking about a budget of €500, that excludes
all the exotic turntables and the typical ones you will find in this price range are direct drive vs. belt drive. Nearly all TT's in this price range are low mass.
Belt drive is typically found in more expensive turntables. This isolates the motor from the platter, and provides isolation from motor vibrations and some damping against motor cogging. Direct drive turntables have more speed stability, torque, instantaneous startup, and are usually cheaper. Belt drive turntables require marginally more maintenance - rubber becomes less elastic over time and may stretch and require re-tensioning or replacement. Direct drive TT's are virtually maintenance-free. You can read more about it
here.
A good inexpensive beginner turntable can easily be had for €500 new - examples are
Pro-ject turntables especially E1 and T1. Also
Rega turntables. There are also many secondhand turntables you could consider and they will easily slip into your price range.
You also need to buy a tonearm and a cartridge. I wouldn't worry about tonearms for now, because most TT's at that price range will have the tonearm included. As for cartridges, you have a choice between moving magnet (MM) or moving coil (MC). MM's are heavier and do not track as well as MC, but they have the advantage of higher output. Nearly all phono stages support MM output. MC's have much lower output. Nearly all high end cartridges are MC. The usual budget recommendation is the Denon DL-103 (MC). New ones cost about €290 so I suggest you look for a secondhand one.
I will offer a rather controversial suggestion: I view turntables as a fun object only, and I do not expect to get high fidelity from it. You
can get amazing SQ from a TT, but you have to spend umpteen thousands of € before it even gets close to digital. It's a bit like a Lomo lens that is objectively terrible, but images from it are fun. So I would choose the most fun sounding turntable, objective SQ be hanged.