Motorbikes and transit (type) vans

Hey guys, hope this is the most suitable section to put this. I was wondering if anyone could answer a question or two, and also gain opinion from others.

After our long summer break I was looking at the awesome roads of Devon and surrounding counties thinking how awesome it would be to bring the motorbike away with us. However it would be selfish on my own to leave the wife on her own on holiday so left it at that. Now my wife is looking to get her category "A" and get a bike too. Now to both go out on the bikes for the day while away would be pretty good fun. 

First thought was to get a motorhome and bike trailer but
A) You don't seem to get as much motorhome for your money, and it's more vehicle running costs
B) We have a lovely caravan anyway
C) Bikes on a trailer would be super vunerable when parked anywhere.

So I thought about getting a small Transit/Merc Vito/VW T4 sized van that we can put the bikes in, much more security for the bikes, going from 5 to 3 seats isn't an issue as there is only us two and pretty much all vans of that size will pull our caravan.

I know the general rule is vans are allowed on sites as long as they're not sign written, is that still the case? Ours would be plain, all I might do is give it some motorhome style striping to pretty up the plain sides. 

BUT what about motorbikes? Of course neither of us are nutters, we're not into loud pipes or any of that. (my current bike is a 600 Hornet). Bikes would be put away in the van when not in use out of sight and not sat on the pitch. We rarely do our own repairs at home never mind on sites so there'd be no tinkering. 

It would just be to add another dimention to our holiday, nice weeks away, lets ride the coast roads!

Any thoughts?