Revell Slant Six model, unbuilt, sealed bags, all there. WIW?

While the eBay listings are interesting, it’s worth remembering that a listing price is not always a good indication of value. You need selling prices for that. Listing prices, or wishing prices as they’re often called, can reflect the needs of the seller rather than actual market value. It might be a good idea to add the models to your watch list and keep an eye on them for a while. If they don’t sell then they’re likely over priced. If they do sell you’ll have a better idea of what they’re worth.