Space Deficiency
I know the feeling well!! Whilst I do not actually 'collect' vacuum cleaners (having only four now IIRC), I do have far more 'stuff' than I have places to put it.... ;-)
If I could be said to 'collect' anything at the moment, it would be Tektronix 7000 Series oscilloscopes and their 'plug-ins'. I have recently made the (very) painful decision to 'downsize' my collection, and here are the reasons, which apply fairly well to vacuums or anything else.
1) The growing collection is tying up space
2) The growing collection is tying up money
3) These are 'extremely' complex electronic items which are now around 40 years old. Consequently, I am attempting to keep a few 'similar' or identical models, in order to have a common 'spares pool', and to get rid of models which have unique parts which will prove difficult and/or very expensive to replace as and when. Several of the more 'exotic' plug-ins which I have recently acquired have come in a mainframe which I don't really need, and while I would love to have 'one of every model', I am aware that it's not really a practical proposition for a person of limited means living on this side of the 'pond'.... :-(
As Steven Wright said... " You can't have everything.... Where would you keep it??? "
All best
Dave T