long time reader, no often poster

we have 2 kids and the mighty L322 is fabulous, if not expensive. regardless, our kids are young and will trash anything 'nice and new'

No 3 on the way and isofix suddenly becomes an issue in regards to safety.
so, short of buying an old espace or debting myself up to the hilt on a lease of something new, what do people do?!?!
multimacs are spendy and also only seem to do newborns in a minimac. we've tried to keep ours rearward facing for as long as possible and 13kg seems a bit small to just be plonking them in a forward facing seat.
Cheers,