Mine are 18 months apart , I got the Phil and teds with second seat ATM I use the combo where toddler is up top and baby lying flat underneath so it's the same size as a single pram you can get the pram and toddler seat on sale sites and gumtree for <$200 it also depends on the baby too dd is very clingy baby so until she is a bit older I tend to carry her in a carrier or wrap and just have Ds in an umbrella stroller