Tow bars etc

[Knackered Mum]

Hi there

I am new to this forum and a relatively new Lexus owner. We have a 2016 CT200h and the new RXL 7-seater. 

I have recently taken up cycling but am too small and weak to transport the huge mountain bikes on the roof and it won’t fit in the cars with the seats up and without taking the bike wheels off etc. 

Don’t suppose anyone knows of tow bars, tailgate bike racks etc that are viable for either car? 

Lexus have apparently released a tailgate 2 bike carrier for the RXL but it costs over £2000 to fit and they could not answer most of our questions about it - felt like they have not fitted them much. 

Would want something that carries 3 bikes ideally and is transferable to other cars eg tow bar bike carrier  

All help appreciated

Thanks