Some of those FB lego groups are a bit crazy.  I wouldn't really bother with them.  Just list it on marketplace and set it to worldwide so everyone can see it.  I've sold about 80 loose and open sets in the past 18 months.  I have been selling more than just lego, so it may go faster for you.  If all the sets are sealed, you really just need to take pictures of the front and back.  Taking the time to list everything will definitely get you a lot more money than going to a dealer.  You might find some people who will want to buy several sets and ask for a discount.

Personally, I would sell them yourself.  A dealer will give you at best 50% of what you could sell them for, but most likely 30% or less.  Write your first listing in Word.  Then you can just cut and paste.  Essentially you just need set number and title and that it is sealed.  I also list the number of pieces and which mini figures are included (many sets sell just because they contain a unique mini figure).

You are honestly sitting on a mini goldmine.  Like I stated earlier, I have sold about 20% of my lego collection and have made about 70% of the MSRP of everything and I still have a bunch of larger sets and rare items that I haven't had a chance to list yet.  You won't regret it if you just take the time.

Sorry for your loss.

First, go to bricklink.com.  Not only can you sell there (I haven't tried selling there, but I have bought random missing pieces I needed several times from sellers there), but they also list all sets with both current and recent sales prices for both loose and boxed sets.  It is a much better pricing resource than relying on ebay.

Second, definitely go with FB marketplace to sell.  There are no fees.  You listing gets set by your general location, so you are not giving out your address.  You can also have the listing open to anyone, so it gives you an ebay type audience.  I have had many people overseas ask about stuff.  Anyone local I just meet in a public area.

While selling everything individually can be quite tedious, don't go with the bulk sale.  You will make so much more putting in the work.  For example, the Death Star II is currently selling for $2500 on average for an unopened one.  MSRP was $299.  There is a lot of that out there for Star Wars legos.  If you have the original Cloud City set, 10123, that is worth $5000+ sealed just because of the Boba Fett mini fig. 

I have been selling off my collection for over a year now.  Started with about 400 sets both boxed and loose/complete.  I have sold somewhere around 55-60 sets.  Just from those sales I have made about 70% of the total MSRP of all 400 sets.  It is worth the effort and if most sets are sealed, it is a lot easier and less time consuming to sell.

TFSB webpage has now expired.  Not that big of a shock, but I guess that finally ends things.

Krahn is holding on.  TFSB website has been stipped to bare bones with only an update screen and nothing about any product at all.  His update is the typical BS that the Bantha isn't his fault, they are only a third company payment processor and that the place in Texas he "paid" to create the Banthas are at fault.  Completely silly since he stated making these things in China.  He also states that there will be an upcoming update on the wave of 13.  I can't believe he is actually still trying to save face on all of this.

Stan Solo has his R4-M9 up for preorder.  His FB post says this and the next item he offers may be it for him.  Also said he would be making this one in lower quantities.  Not sure if this is just his typical rants or not.

I received an email from Hasbro this weekend saying these were delayed until November.  Seen quite a few people in the UK receiving the sets.

Just a note, even if you preorder in UK and live in US, you will be charged the UK shipping rate, but the item will ship from the US.  That being said, I have begun preordering some stuff in the UK.  I've held off on the last few minus the Tonnika sisters because I'm beginning the process of moving and didn't want to rock the boat with an address change mid preorder, which I might still have to do.  Greedo is shipping.  However the first couple shipments have been solely preorders.  It has not gone up on the US site yet as in stock.  I have waited on that one, Degobah Luke, and removable helmet Vader.  However, I should close this Friday and might preorder the latter two once I have the new address.  Old house isn't on the market yet at this point, but these preorders are just unpredictable with shipping dates.