I've got a Spectrum +2B (the final revision PCB Z70833 Rev 4, dated 1990 - so the audio is fixed compared with earlier models) that includes a DivMMC Future (with an official 4GB card loaded with games), a CoolNovelties Spectrum Start cable, official Sinclair PSU and a bundle of Spectrum games. I'm thinking £175, including postage, would be a fair price - the DivMMC Future alone is nearly £70 when you add the official SD card and the postage is going to be a bit as it's quite heavy. Recent eBay prices show they go for around £130 including postage, but without the DivMMC.
If you're getting back into the Spectrum, the +2B is IMHO the best model to use. The build quality was really good, it's reliable and while there were issues with the +2B not loading some games, I've included most (if not all) fixed versions of those games on the SD card, meaning you can play them anyway.
Everything works really well and it's in a great condition. I'm selling it because I originally bought this waiting for the Next to be delivered. Now that I have a Next, I can't really justify having it and need the space. To be honest, I've found this +2B to be more reliable at loading games from the DivMMC than my Next is!!!
I can post pictures if there's any interest in it, otherwise I'll sell it on the dreaded eBay!!
Thanks!