Ellied, my experience has been this -
Down in England, a long long time ago, our smallholding was a caravan and camping club certified location. When we started all that was required was a tap in the field where your guests camped and somewhere to discharge a chemical toilet. We did this for a couple of years then the c&c club changed the rules. As I remember, a change to insurance was needed and (I think) more facilities for bathing/pot washing/wc. For the amount we got per year it didn't cover any of the costs associated with the upgrade, so we stopped. Now, moving to Scotland, we thought we would try an upgraded site with what are now referred to as glamping pods. We contacted the council and they said yes! Please submit your plans and they will be passed - after all, we need tourists in the area. So, a few months later after a very expensive trip to the architect we submitted the plans only to be told that despite the need to bring tourists to the area they must be able to get to us by public transport. What a farce! Needless to say we are a good 4 miles from any bus stop so our plans were scunnered again.
Don't let my experience put you off though take a look at this site down on the farm.net
although this is a farmer and his wife who run the site with, no doubt, grants etc for diversification etc it shows what can be done.
I seem to remember though that the planning process wasn't a walk in the park.
good luck if you go ahead - have you spoken to the council yet?