Thanks for the reply.
I think it is either Option 1 or Option 2.
For Option 2 - would it be the following:
https://www.halfords.com/motoring/roof-bars-roof-boxes/roof-bars/thule-roof-bars-761-pack-of-2-625350.html
Then three of these :
https://www.halfords.com/cycling/bike-racks/roof-mounted-bike-racks/halfords-roof-mount-bike-rack-635780.html
Struggling to find any rear boot ones that fit for Option 1- we wouldn't be using it often, more for getting the kids bikes around.
Thanks
Iain