How quickly to babies grow?

This is my first and i’ve been like obsessed with buying clothes and most of what i’ve bought was used and cheap anyways like hand me downs from people but I dont wanna buy more than necessary. I have probably 100 things ranging from NB to 0-3 months but not many 6-9 months and so on. I hear they grow quick and grow out of newborn stuff rather quickly but as far as 0-3 months I dont know if I need more stuff than I have or not.. I dont have too much but even if I did a new outfit every day wouldnt hurt right? 😭😭