Double buggy for heavy child!

[mayblossominapril]

I have a 16kg four year old and a 9kg one year old and I think my old city mini has given up on me!
A double will probably be needed for another year as DS 4 is a bolter, is overwhelmed and can't cope in shops and we walk long distances. We have tried a buggy board and it doesn't really work for us.
I really need a buggy that will take up to 22kg plus dd who is growing.
Someone on a previous double buggy thread linked to one that easily converted from a single to double but was about £600.
Any other recommendations?
I have an estate car with a large boot. Something that is reasonably capable off road would be good. Ideally I don't want to spend a fortune

Phil and teds sport

The Out n About Nipper Double is great. Can pick them up second hand for £150-£250 depending where you are (Usually on marketplace but selling pages on Facebook too).

I second the out and about nipper. Very strong buggy. I’ve had a heavy 6 yr old in it and it’s survived!