Do I need a Certified Accountant? - Public forum - Planning Advisory Service (PAS)

We recently got planning permission for two mobile homes on our land, agricultural tied. This year we are going to put in permission to build. The query is with our last application the Rural Advisor said we should have a certified accountant, I pointed out that I did the books myself and that HMRC where satisfied with that, so they let it go, Do we have to have a Certified Accountant?