It's worth as much as anyone is willing to pay for it. Sounds a bit of a put down, but don't take it the wrong way. Alot will depend on where you advertise it & to what lengths you are willing to go to, in order to sell it. It's a big world & shipping Internationally from the UK is very very expensive (why?)
You might also accumalte more selling Key Items as individual Items. Lots of usually sell for less unless you have a real hard-core Amiga-Nut gagging for the whole tomali. :-D
The Picasso IV is worth £150 alone if it has it's flicker fixer as well. The A4KT is definately a possible £500 on it's own as a Standard A4KT.
No dust & shiny lustre will also add to value & original boxes make them Ideal for Collecting Coniseurs! :roll:
A shame you're selling but best of luck however it goes for you! :-)