Must be:
powerful
good with dog hair & sand, mud from little boys
long cord
large capacity (preferably bagless, I think)
store tools on board
not too heavy (I have ME so get very tired very quickly)
I loved my Miele pull along one but got fed up with the small bag filling up with dog hair every time I used it. I replaced it with a pull along Hoover which is ok but nothing is as good as my original, British made Dyson DC01.
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Hello!
We've noticed this thread is quite old and some of the product recommendations are a little out of date. We've spent weeks speaking to parents and testing out vacuum cleaners, so here's our round-up of the best lightweight vacuum cleaners available to buy now.
Hope this helps! 
MNHQ