[Closed] Used laptops with reliable warranty ..where from?

Need another laptop as my ancient dell is struggling. Nothing flash required . Would normally buy something from John Lewis for the 2 yr warranty as they've been good in the past but it seems you have to spend 500/600 for anything reasonable and I don't have much income so thought about buying used instead. I could buy privately but am wary of unscrupulous sellers shifting faulty kit so wondered if there are any reliable vendors out there who sell half decent used laptops at a reasonable price with minimal quibble warranty.
I would appreciate any recommendations or other suggestions
Many thanks in advance
Bill