I sorted out the loft before we started and gave away a lot via our local "eco community" group (I had several pairs of curtains and some throws, for example, that we wouldn't reuse now as we have shutters and have changed decor). I've also given away the dining chairs (DH currently has the table as a temporary desk), and some other bits we aren't reusing.
It's more just the volume of kitchen stuff surprised me, just how much there was in 4 base units and 4 wall cupboards! I'm using heavy duty plastic storage crates so I think partly its just that they are bulkier than I realised. Trying to use things like tea towels to wrap stuff / fill gaps to save space.
Some things DH has packed without sorting - spare lightbulbs, for example - as I just don't have the headspace to work out which ones are for current fixtures, which will fit the new fixtures etc. We'll sort that out when we unpack!
DH also forgot to label the crates he packed (he has ADHD) so I have half a dozen mystery boxes 
Finally got a price for digging up the kitchen floor, new concrete and insulating - £1700, so not breaking the bank, thankfully. Now to wait & see what price Howdens come back with for the units and whether I am up to haggling at 40 weeks pregnant 