Phil - anybody who makes an offer on the whole lot is going to want to make some money on their purchase, because there is no way they are going to want to keep every single item for their personal collection. In other words, you are going to get reseller offers with a lot this size. You should expect to take a large loss selling it as one big lot.
The only way to make sure you will get full value for everything is to break it down and sell every game and system individually. This will take significant time and effort compared to selling it all together - it is up to you whether or not it is worthwhile to go that route.
My offer stands, and I am always open to negotiation.
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