Chariot is expensive! I bought a secondhand Croozer and quite happy with it .. actually, I’ve just looked at the prices new, and there’s not a whole lot in it between those and the Thule. The Chariot Lite looks interesting – these things are quite big and bulky, even the single seater I have.
If you’re not wanting to spend loads of cash and unsure it’s going to get used, look out for half price deals on Halfords trailers. Can pick them up for £80, probably not quite as robust or weatherproof, a lot of people rate them and they actually seem relatively small and compact.
One thing to take into a account – for baby stuff generally – is resale value tends to be quite high.