Apparently, the late 2013 13" and mid 2014 logic boards are interchangable. According to this page, https://beetstech.com/product/logic-board-a1502-2013-2014, compatibility is set to late 2013 and mid 2014 models. The board in my late 2013 died and I found an eBay auction for a mid 2014 with 8gb of memory (my old board had only 4gb). I won the auction for ~$180. The cheapest way to get a board is to find an auction for a used one on eBay. Unfortunately, board auctions are few and far between but, generally, a comptible one crops up every couple weeks. If you check the site for new auctions every day, you'll eventually find a board that will probably cost half as much. There is high demand for boards which has caused the prices to skyrocket. Auctions generally force them to sell at the price that we actually find reasonable.