I think that insurance companies prefer the MH on a drive which reduces the premiums. So I'd ask the insurance co. which option is cheaper for you, in a compound or on the street then work out total costs. Guess it depends if you think it's "at risk" on the road outside your house.
If it's actually in the road there is a risk of it being hit by passing traffic, or as happened to me at a previous address, having the mirrors pulled off and the doors kicked in by drunks.
A compound is a better idea as it does shout to the world that your house is empty when you are away.