Recommend me a bike rack for a scenic (post 2009)

[VEX]

So, wife and I have MTB's, mine if full suspension and hers is front only.

Just bought daughters two new bikes for the summer, one 20" and one 24" wheel.

So now I need to carry them on our Renault Grand Scenic (post 2009)

I already have a pair of Altera Giro Speeds for the adult bikes, which I used on my truck with bars, but wife may not be willing to get her bike up onto the roof.

So I am thinking of a rear mounted, three bike system to hang her's and the two kids ones on when she wants to take them out some where.

Or do I bite the bullet and just get a 4 bike rear or even another pair of roof ones and some roof bars for the scenic.

No tow bar or electrics and I don't really what to go through that cost.

V.