Im sorry to hear this. There was a huge report on logic-boards of these models failing because of bad ventilation in this model. It is most likely its hard drive (which is soldered on the logic-board). I would take it to a [link|https://montrealmacbookrepair.com/|Macbook repair] shop, or contact them to see if they have any information about them.[br]
[br]
In general I wouldnt spent money on this model if its gonna cost more than a few hundred bucks because of all those bad reports.[br]
[br]
Sorry if this wasnt that helpful.