Hiya 😉.
So I bought my GSF during lockdown. All over the phone and email, from just photos videos and conversations.
As other people have mentioned yes you have 14 distant selling regulation which will allow you to return the car for any reason.
You also have statutory consumer rights which means that if any faults occur within the first 30 days you can reject the car for a full refund. This is covered by the consumer rights act.
Haggling on price is very minimal I noticed but I did try buying two cars from two different lexus dealers and got two very different services.
Hull refurbed all my wheels, replaced breaks which didn't really need doing I was just fussy, gave me new tyres (none of the old ones were at limit ), had the body work machine polished to remove any swirls etc, they also offered me more on my trade in by nearly 50%, paid for my admin costs, delivered the car for free to Colchester from Hull, organised me a replacement card key which was missing, gave my next service early(so gives me an extra year cause I won't be mileage related servicing lol) and finally didn't try to hard sell me everything under the sun. For the record I took 0 add-ons.
Coventry however.... Refused to do anything
Would recommend trying a few different dealers