Well, if you're saving for a new place I have an idea for you in the meantime.
I have more clothes and shoes and bags than is necessary and I most certainly do not have room for them all, so every Autumn I pack all my Summer clothes and shoes in suitcases and take out all my Winter get up and vice versa.
I used to put the cases over to my Dad for him to store in his loft, but I have my own loft now.
If you both do that then that's one problem solved - you can pick up the cases pretty cheap in Matalan or the likes, it's not like you need it to be durable like you do for actually using them for going on holiday.
What else are you concerned about? No furniture (tick), out of season clothes out of the way (tick).
Books - have a proper clear out and only keep the ones you know you will read again, the rest can be stuck on e-bay
CD's - Get yourself an External Hard Drive and load all your music on it, then either store away the CD'sor sell them on ebay for a few quid each. To listen to your music, you can buy a thingy (I have no technical terms!), that hooks your Lappy/PC to your stereo and listen through that (I don't even have a stereo, I hook my lappy to the TV and listen to music through the surround sound system). No lappy? That's OK, with the money you are making on e-bay, get yourself an MP3 player and docking station, I'm sure a friend or relative won't mind you poppng in now and again to hook your EHD to their system for you to update the MP3 player? Docking stations are surprisingly loud too! I was shocked!
DVD's - Buy a DVD book thingy (I'm sure making full use of the word 'thingy' today, I think I should get royalities) and ditch all the DVD boxes, this saves a load of space.
Have I missed anything?
I hope some of these suggestions are a bit helpful x