If you can, have a look at Witters offerings to see if they do a bracket with a detachable ball of the British (i.e. flage with 2 bolt holes to hold the ball) type.
I suggest this for 2 reasons
1) when the ball wears out its about 20 quid rather than 150+ to replace!
2) I have more faith in the security of the flanged fitting towball rack (using a plate that uses the two bolt holes) than the modern type that clamps onto the towball.
I used a Witter bike rack - the simple one, similar to the ZX*8 for years and was quite happy with it, but did NOT use it while towing the caravan at the same time because
a) It takes up noseweight e.g. if the carrier + bikes weigh 20kg, and your car has a 75kg noseweight limit, then you can't put more than 55kg onto the towball, and this may be too low for your caravan (assuming you have one!)
b) When tight maneouvering, there's a high risk that the bike wheels will become trapped between the rear of the car and the caravan front end/gas bottle locker etc.
You will need a lighting board 'cos the cars rear lights and number plate will be obscured..
Of course, if you are not towing you can save a huge amount of dosh by having a detachable rack, I would recommend the Saris Bones. This also means that you won't have the potential depreciation on your car associated with having a towing bracket on it, nor will you have to keep checking that the bolt holes are properly rustproofed!Nor, if the car is new, do you have to worry about approved manufacturer fitting and parts so as not to invalidate the vehicle warranty.
BE AWARE THAT SOME VARIANTS OF CAR MODELS ARE NOT APPROVED FOR TOWING SO CANNOT HAVE A TOWBAR FITTED - When I bought our last car I found this, certain models of Focus, Astra and other cars could have one fitted, some could not. Often the sports and eco versions cannot so you do need to check the specific car you are thinkiing of buying. How to tell? 2 ways
1) does the brochure list a towbar as an accessory, and does it give towing limits
2) The plate that you'll find onn the car somewhere giving axle loading - I'll leave you to look that one up here https://www.towbarexpress.co.uk/maximum-towing-weight/
I do carry a bike on an MX5 with the Bones, its a 2007 model car and in this case required no sophisticated electrics for the lighting board (the cable coils up in the boot when not in use) .
Brompton, Condor Heritage, creaky joints and thinning white (formerly grey) hair
""You know you're getting old when it's easier to ride a bike than to get on and off it" - quote from observant jogger !