Normally, Booking & Agoda have same rules, I don't think one is better. Many times, hotels are cheaper on those sites rather than contact them directly. In my experience, I booked a wrong date one time, & Agoda didn't charge me to modify the date, because the hotel agree to do it.
So, retirement visa you pay around 15.000 baths & you have to go many times & make fotocopies,, Elite visa, you pay 600.000 or 1 million baths not refundable, without fotocopies & visiting inmigration in 5 years. I prefer to move my ass. Second option is expensive.