Even excusing used hardware you can litterally buy brand new ready to go windows based pc's in that price bracket.
Prices from Pimoroni. The price of a Pi 500 is £84.60 for the unit + £11.40 for the PSU + £3.90 for a micro hdmi adaptor (which I'm adding because almost everyone will need one). Giving you a total of £99.90 plus shipping. You'll also probably need more storage as it only comes with the 32gb micro sd (down to about 27gb after OS space) but I'll exclude that from this for now.
- For £74.99 including delivery & PSU you can get a Kuyia Win10 Pro Celeron J4105 mini pc with 8GB rand and 256gb SSD.
- For £80 including delivery & PSU you can get the GMKtec G3 N100 with 8GB Ram, 256GB SSD, or pay £10 more an get 16GB Ram, 512GB SSD.
Theres so many of these around now. I know people have a soft spot for the Pi but it's really not the best option for most applications, and hasn't been for a long time now.
All of these, for a desktop experience are better. All of them have hardware Windows licenses should they be wanted. All of them support Linux, all of them are upgradable.
Unless you need GPIO the prices just do not make sense, and if you're willing to buy used/refurb the leap in specifications is even higher.
I am the person you replied to. And I have personally bought brand new Lenovo and Dell mini pc's on ebay in that price range. I only didn't mention them in the follow up comment as they are admittedly snapped up very quickly so you do need to be on it to grab one.