Instead of feeling the need of getting someone in to tell you don't need all the stuff cluttering up your home , what makes you feel you need to keep it ?
Tbh it just takes the motivation to start , you say you want a nice home for your daughter , that's good motivation , also it will make you happier to have a cleaner , clutter free space you love as well .
If you haven't used it or if clothes worn it in a year , then it's probably time to get rid .
Don't keep stuff because you might need it one day , or if it was expensive, remember if it doesn't get used , get rid
If you have doubles of things , keep the newer item , or the one you like best , i.e mugs , we have our favourite ones , but the more expensive you keep for visitors , or best stay in the back of the cupboard . Which of the two types do you want to keep ? Favourite or better quality ?
Same with clothes wear your best shoes or coat , get rid of the tatty old faithfully carry on wearing.
Don't keep stuff for sentimental reasons if they don't have a purpose , if it was a gift but isn't quite what you like , get rid , your daughter's baby clothes , get rid , same old toys & teddies etc , encourage her to let them go.
You can take photos to keep the memory .