Advice in buggy for newborn and three year old please

[jai38]

Any ideas on a buggy to fit the following criteria?

Lay flat for baby but seat large enough for three year to sleep in for nap (whilst baby in sling)
Can attach a buggy board sensibly - I am short and live on a very steep hill - so would prefer not to be bent over awkwardly
Has a good UV cover as we are on the south and spend a lot of the summer on the front
Price - am expecting to pay around £500 but for this want it to last.
Dont need carrycot as won't fit in the car with three kids , fitting a car seat would be good as well.

See I don't want much so any advice gratefully received please

I would say have a look at the Baby Joggers - City Mini, City Mini GT and Elite. I am wondering if the last two might work best with a buggy board as they have a rotating handle and the child might fit in between the hod and handle. But I haven't tried it. Or something like an Uppababy Vista with Piggyback or Rumble seat? The Vista carrycot is included but squashes flat in its own bag for storage.

Hood ^ not Hod

Thanks we have local independent that stocks both so will pop in with said three year old to try