Do you plan to keep these children as they grow, or will you always care for multiple children under 3? For me, I have 3 children under 2 right now, but I don't plan on taking on any other infants (as my 1yo grows, I'm transitioning to 3+ preschool). So I opted for a big wagon that is versatile as they grow, and it's just for the 2 youngest (one tentatively walks, one crawls). The others walk alongside the wagon.