Laptop troubles

So, my brother was recently the victim of internet fraud. He sold a computer online and delivered the item. The person sent the money but then took it back somehow. Instantly lost one thousand dollars. Ouch. I am looking at reconditioned laptops and really hope I don't run into similar issues. I figure if I get it from a really well respected place then I should be okay. I can't wait to get a new computer! Mine is getting so old and freezing a lot!