Arguing about the extension fee is a waste of time. Firstly, the first application for extension is about 5 months away; secondly, there is a lot of misinformation and unknowns surrounding it; Thirdly, I and many suspect there will be huge changes over the next 6 months - 1 year regarding the DTV
I've been informed by reliable immigration officers I know that they have been informed to check both finances and appointments on reentry not just when someone is applying for an extension
you can visit all the embassy websites and I guarantee you that most of them will state different rules surrounding visa exemption. I mean heck even embassies within the same country have been found to state different things and have vastly different requirements for visa applications.
The only 4 year ED visa you're getting without having issues is from a university. I am 1000% sure you will have major problems at any and all airports in thailand if they see 4 consecutive or even spaced out ED visas from anywhere but a university in the system or in your passport.
regardless of what visa you have, non-b, Non-O, non-OA, non-ED and even the new DTV. If you are in the country for more than 90 consecutive days you need to do a 90 day report.