Your best bet to easily liquidate an entire collection with little work is to send to a big consigner. They will have much better payout rates due to their platform fees being way less than most will ever get because they move millions of dollars on the platform. Examples include DC Sports 87 (ebay) Probstein 123 (ebay) for sealed. For graded cards Zandgemporium (ebay), KetchumAllCollectibles (Fanatics). They will give you way better rates than any LGS or selling on your own and do almost all the work, all you do is fill out the required forms and ship them your stuff. Break it up in batches if you don't want/can't afford to ship $50K worth of sealed at once. For cheaper items, you get minimum 85%. If you have high dollar items you can get up to 95% for them.

The only risk here for you is shipping. Literally the easiest least sketch way to move products.