Excellent question! There's no wrong section to ask a question on Bloomilk;
and hopefully you'll still play the game one way or other

As to value... That depends on a lot of things...
is it sold separately or all together? has it been accredited as A1 by an auctioneer/grader etc...
Don't take the 'buy it now" values from other places such as MillenialMinis, GameHollow, TrollnToad, Nerds And More etc as gospel hehehe,
as independent auction or sale and consignment selling or swapping are a little different

with that in mind, we can only go off of what has been realised at recent places or from lots at Ebuy etc...
I've seen sets go for, mint in bag with A1 stat cards,
$2-300USD for a whole set,
1-200 for a "fair" as played as is collection set,
and 40-70 for a "poor" condition set with damaged cards (say, severe fade, damaged edges or tears)

by that reckoning, and adding in the scenario books and Endor and Hoth sets etc...
assuming they were A1 grade, at auction or 'buy it now",
it'd be 12 x 300 + 50 (for mint scenario books) + ~200 (for all mint sealed league promos) + ~80 (for mint sealed ATAT) + ~ 50 (for mint Endor)... = ~2-3000USD, +/- 30%, 5 sigma.
2-3000 is a fair ballpark for a complete mint collection, inclusive of deck protectors and storage etc. A little more might be realised if there are signed minis, customs etc... or other 'memorabilia'.

That is just going by previous sales the past 7 odd years, so please use this info merely as a ballpark guide and with the appropriate bags of pool salt...

for contrast,
a Darth Vader themed promotional fridge from circa 99,
cost 200,
and went for... 8000 locally recently.
A jarjar maquette from Pizza Hut, cost ~300
sold for $85... yup. Not only unpopular, but no-one had storage space.
(The purchaser intended to color the lot pink and use it for target practice...)


Now, whether your lot reaches that value, or whether your own valuation is anywhere near that,
that's a different matter hehehe.
If people are angling for kitsch or 'its rare' value... (so, some extra multiplier percentage, say " + x 50% value, coz it's rare" ) sadly, it was mass produced and is not yet as rare,
it was also made from a flimsier plastic, as compared to other comparable costed items which have come on market.
However, the inter-operability with FFG's Imperial Assault has seen a spike in values on some minis elsewhere.

Good luck! And, if you'd be awesome and share roughly what it went for, that'd help immensely for other folks in future who might have similar questions (or, want a ballpark figure for insurance on their minis etc)

In any case I would offer $1 for the AT AT now if you don't want to bother with an auction.

indeed... 1200-1300 for a bulk lot such as that all at one time, complete set every mini in A1 condition,
it is a reasonable price...
71C per mini is a *cough* ripoff *cough*, but it'd be a great deal for them

an offer is just that, an offer, I'm sure no insult was intended.
emotions must be kept separate from selling
not many people need a huge lot of complete sets of SWM.
those few still playing, need a few pieces to complete their collections, or some pieces they have been waiting on the price to drop.
this games been dead, as long as it was alive
any new players,do not equal players leaving
too many hiny new Stae Wars game to compete with
IA skirmish combat is superior to SWM.
I believe the prices for SWM has peeked
expect to get $1500-$1650 for your lot on Ebay
piece it out, and get closer to what you want.
good luck selling

I've only bought in bulk, never sold that way personally, but I think what others have said above is about right. Now, granted, some of the sets (such as BH, CS, UH, some of the rarer earlier sets with more pricey pieces) CAN grab a good $200+. However, other sets (such as IE, probably JA, some of the later sets with less and less rare pieces) may struggle to sell for even to $100, even separately, in my experience.

I think even selling them separately by set (they can be broken up MANY other ways, however; by faction, thematic groups, pieced out to users or on buylists etc.), you'd have a TOUGH time getting near $3,000 once they sell, and even then may have to take fees/shipping etc. out. I've bought many a bulk lot over the last few years, as mentioned above, and I think the ~$1500 mentioned above for the whole deal at once is probably at the top end of what they may be worth.

Now, if you happen to have duplicates of some of the desireable pieces (multiple Rancors, CS Destroyer Droids, Uniques, loads of Stormtroopers etc.), then you could very well prove us wrong and get quite a bit more than what everyone here has said, but if that's not the case then my opinion is that they're probably worth closer to half of the 3K.

Hope this is helpful!