In-box seller tips, someone who needs to downsize

Hi gang, I would love your advice if possible. So even before Covid I started collecting, Marvel Legends, diamond select, Mcfarlane, Fuko (especially Rick and Morty, marvel, DC), funko boxes, pokemon unopened packs, star wars black series both figures and helmets and random other things that appealed to me. During and after Covid it got ... a little out of control to put it mildly. I keep everything, at least 95, in sealed sterilite free from as much damage a possible. Im talking ballpark something like 500 figures. Idk I would say 30 full large 32 to 64 gallon sterilize. I had planned to do a crazy room one day with extensive displays. The problem is my ex ruined it by belittling me for my childhood proclivities and now I just kind of want to do something smaller just formelf. When I was a kid it was so hard to get the figures I wanted so I went a bit overboard, and for awhile it was great. I just loved having them for my inner child. But now on top of wanting to downsize for moving purposes. I just kinda only want what really brings me joy. Sorry for the diatribe and thanks for listening. Now the questions, im not a scalper a but I would like be fair at least somewhat to myself. I've tried selling on ebay but after their cut and shipping cost I feel like I can't or can barely get even close to what I paid or what the current value of even my rarest figures. Mercury doesn't seem much better and facebook marketplace can be very sketchy. Any suggestions, like is there a good shipping app to pair with Ebay that's worth it? I know im going to lose some money but at this rate it seems downright unfair. I feel like with these costs maybe I should just sell to a store or something IDK. Help please 🙏