Does anyone have any experience in fitting 3 carseats in a row? Which carseats do you have and what vehicle?

I have 2 toddlers and will have a newborn in July. Trying to figure out how we can manage this. (Looking into buying another vehicle but it wont have a 3rd row) Both of my toddlers are still rear facing but plan on switching my oldest (will be about 3.5y) to front facing when baby is born if that makes it easier. TIA!