Hello Andy,
I like your idea of selling retro handheld items, in fact I like that idea a lot, nice one.
As a side line I used to sell TV repair kits, mainly for T-Con boards and power boards. I did quite well selling blink repair kits, especially for the Panasonic 11 blink issues and also Sony TV repair kits with fused resistors, all the components I brought in bulk mainly from China, some of the Sony components came from a supplier in Vietnam, yes I know how strange that sounds. I also sold working used TV parts from TVs that I couldn't fix or were not cost effective for me to do so. For example if the panel (screen) was damaged, I would check and sell it's parts on eBay like the main board, power board, T-Con etc. If need be I would change/repair faulty parts before selling the boards . You may have seen screenshots of an Android app that I created just so that I could take photos of the parts and log part numbers of working boards that I had that I could sell, I also logged the make, model and TV's that that board would work in.
Many years ago I used to go to Biddle & Webb auctioneers in Birmingham to bid on computer/tech/some electrical items just to sell them on eBay, now and again I would come across a right gem. For example I brought a box of basically what I thought was cheap computer bits, but sitting at the bottom of the box was 5 CISCO routers, they sold for a lot of money on eBay, I won't say how much but I was completely surprised when they made 4 figures (each) and people just kept bidding, I was hoping to get £200 to £300 for the whole box.
I also used to go to an auctioneers in Coventry, once again to bid on computer/tech/some electrical items. Over time more and more people started doing the same thing pushing up prices at the auctions, so I quit doing that.
I also used to buy from the auction below, police auction. But they stopped selling on this site and started using eBay, that's when their prices shot up.
https://www.bumblebeeauctions.co.uk/XcAuctionPro.asp
Another reason why I stopped selling on eBay was the fees started slowly creeping up on eBay and Paypal.
Right, I'm going out for a quick bike ride now, it's dry and I can get a quick 10 to 12 mile ride in before going to bed.
Those were the days 
