For hobby or children’s use there are a wide variety of microscopes available on Amazon or eBay that represent excellent value for a low budget. The majority of these are manufactured in China and the quality and value continues to increase. Up until about 2015 we recommended good quality, used microscopes from European or Japanese manufacturers but the price point for those has dropped so low that we no longer carry those.
The only recommendation we make now on used microscopes is that you try before you buy. There are a number of things that can go wrong on old microscopes, particularly optical alignment, lens delamination and fogging, zoom mechanics freezing and focus mechanics wear and freezing.