Whilst having lots of ram is preferable, I can still do everything a regular desktop user needs to do on a 1GB ram laptop running Devuan, including internet using Firefox browser, it can be a little bit slow at times, but is perfectly usable.
So, I'm just making the point that even a somewhat slow laptop is still very usable, if you run Linux on it.
Also, the Raspberry Pi SBCs are very usable as a desktop computer, if your needs are not too taxing, & they are really much cheaper than most pre used regular PCs or laptops.
Think about what you are wanting to use the computer for.
