@Kool ******
Your last sentence describes the inside Thailand 90-days Non-Imm-O Retirement Visa application by a "change of visa type" from out of a Tourist Visa, which STRANGELY in the sentence before (!!) you mentioned wouldn't be needed! You actually are contradicting yourself.
The fees are, correctly, 2000.- THB for the initial change to the 90 days visa application, and further 1900.- THB for the application to the 1-year extension.
However, you forget to mention that when doing the "change" with an 800.000.- THB deposit proof, one must show that the money had come in from abroad.
With the only exception being Jomtien Immigration, who don't ask for the proof that the money came from abroad, but will always ask for a 2-months seasoning of the 800K for the application to the initial 90-days Non-Imm-O visa.