Returning a car to the UK

I know you have to export it and return the number plates. I don't know where you are but if it's in Marche then Nicola at Fioravanti & Pavoni near the roundabout in Comunanza is very helpful and can do it for you. No doubt you will have to pay.....

This link, from the ACI site, gives all the details you need to know - http://www.aci.it/i-servizi/guide-utili/guida-pratiche-auto/esportazione.html  

As you have gone through the rigmarole of registering it in Italy you should be able to sell it and get a better price than it's value in UK even if it is RHD