Earlier quoted context omitted.
The way most people in Germany would solve this (we need a potty for some months) is buying it 2nd/3rd/4th hand. Is that not common where you live (I guess USA)?
The problem with 2nd hand is convenience. Maybe I can save a few bucks browsing eBay etc. but it’s not worth the time spent compared to ordering new. I hate doing it though.
If you know "oh, we will need larger cloths and a potty and some toys soon and that bed will be to small in a bit" you can monitor relevant sites on the side and see when the opportunity comes up.
Not to mention the social circle with parents a bit older and a bit younger. "Hey, we don't need this anymore. Do you?" - "oh it's a bit early, but I take it already thanks!"