My friend will come in Chiang Mai and ask for non-O Visa 3 months. He will have a rental agreement for 3 months in Chiang Mai. After this 3 months, he want to ask for an extension 1 year but he will not have rental agreement as he will go live with a friend who has a house, but this house is at Nakon Ratchassima. Is it an issue, does he have to ask the extension at Chiang Mai or Nakon Ratchassima? And can he use a copy of house registration of his friend ?

Thank you !