A lot has to do with how fast you want to move them.
The problem with consignment and/or selling to a dealer is you are going to take a bath on what you get. Dealers need to make profits to stay in business and will only pay 50 to 60% of value. Consignment has commission (usually 15 to 20%). If the consignee tacks their commission onto what the gun is worth, it won't sell.
Individual sales are the best way to maximize your take, but a lot depends on local prices if you want FTF. Another thing, even with local FTF, if a buyer offers to buy a batch from you, he will want a quantity "discount".
National auctions have a commission to pay (10 to 20%) plus you need to ship them the guns. If some of them don't sell, you need to pay to ship them back. And if you don't use a reserve, be prepared to take some losses.
Selling through internet, (auctions or via gun boards) has its own inherent problems. You don't know who you are dealing with, shipping is a hassle. If the gun gets to the buyer and he finds some thing he doesn't like, (it's easy to find a reason to squelch the deal regardless of how many pictures you take or how good your description is) you will have the hassle of getting the gun back and the buyer will usual expect the seller to pay the costs.
(Handguns are especially expensive to ship.)
I’m currently facing the same problem as you. I am in the process of disposing a collection of a friend that consists of 44 guns. They’re mostly antiques, so the shipping isn’t too bad, but I am going to go with local sales to start with. He is in no hurry, so I have all the time I need to hit the gun shows and do some local “word of mouth” advertising. After that, I haven’t decided which way to go. They may show up on-line in a couple of months.