Have a 96 +4 4 seater in london, but not sure how insurance would work with hire...
Most Insurance companies exclude "Hire or reward" if you can find one it will be expensive !
So for a private person to hire a car out for use to a third person on a public road is a "No No" on expense alone
This is why garages charge about £195 per day for car hire or £950 per week.