Living in a relatively rural area certainly has some advantages, and now that we have completed a major phase of our project, we have applied for and received our tabien baan (house registration book) and confirmation of our postal address.
We never applied for building permission simply because we had faith in the local rumour that we did not need it - but safe in the knowledge that a small back-pocket fix would put things to rights if it turned out not to be true.
Sure enough, the rumour machine rang true, the house registration book was delivered without a murmur by a young girl employee of the Tambon office, who fulfills the function of Or Bor Dor amongst others - such as preparing the monthly water bills - and at no time was there any mention of wanting to see the blueprints or any other construction related documents.
Cost of the excercise?
20 baht.

See the pics and full story of the construction of our amazing low cost house in Thailand.
and How it all started
See also: Getting Connected with electricity.