I've sold quite a few items on ebay - incl. expensive scopes etc. So far no issues.
But a few pointers:
1. I sell only cheap crap
at standard rates. I have a list of more expensive items I list when eBay sends out the "seller specials" where you only pay GBP 1,- or 1% per sale. So I pack everything up and write the text and pictures - and are ready to post when eBay sends their special offer. (Only works with things that does not depreciate quick....)
2. Always have pictures of the ITEM itself. For fast postings just use eBay app on your phone and snap some pictures. Even bad pictures gives me better prices on auction than stylish ones or original manufacture pictures only. It also protects you as seller. If it is electronics with "display option" show it working somehow. I have a standard text on my adverts saying "If it is not shown in the image or specs it is not included"
3. To get the best price if you are in the UK - you must ship to rest of EU. It usually gives me 10-30% higher end sale price. I usually exclude the "EU Newcomer" countries as that is they only places I have had attempted "fraud" from. Sadly you can't save your seller preferences for countries so you have to actively go and select countries you ship to manually every time.
4. Try and guesstimate the potential market before you list it. I sold my Tek MDO via advertised price and "best offer" enabled because market is "small". Other items that has a bigger market - does a lot better on "No reserve / GBP 1,- start" than if you put reserve on or a high'ish start price. Sometimes I do make a bad call and sell something too cheap - but usually it reaches the price I expect or more.
But I am amazed by how many people will pay up to normal retail minus a few pct for 2nd hand products. Some buyers on eBay are just "shopping mad" I think.
But sometimes one can be really lucky at get the right product for the right price or dirt cheap. That was how I got my MSOX4k...