Anyone have any recommendations for particular models, sizes ? The Skoda roof box and bars seem pricey. Need something to fit some luggage in whilst taking the parents on holiday with Mums mobility scooter taking up the boot space.

Can't help with roof boxes I'm afraid, but I've used Thule roof bars for some years now. They are not cheap, but neither are any good makes and I use them because I carry Canadian canoes which generate much wind lift, so I need good kit. A roof box will also generate a lot of wind lift too.

I've also seen Yakima recommended on these page recently, but I have no experience of them.

Have a look at these people  https://www.roofbox.co.uk/. Put your vehicle reg into their search engine and see what they recommend. You can either buy from them, or once you see what they suggest you could look on E bay for the same kit in used condition.

I bought a roof sized Thule Ocean 80, 320ltr. front opening box, for my Fabia Estate and roof bars from an Amazon seller but do shop around.

I also bought the Thule shaped bags to keep things easily loaded and unloaded.