, I am not a native English speaker but you say 'application'. You not do any 'application' with border hops/bounces. You come in on visa exempt, multi entry tourist- or non O multi entry visa. The only difference in my knowledge is that you can do this by land borders only two times a year with visa exempt. And another difference is only the imm. officers themselves. Does not matter by land or 'by airport imm' coming in. They can be giving you a hard time or not.
: If you want a Taxi instead of bus or train, I always use 'the trick' after coming in the arrival zone, to go upstais again to the departure zone, go out and go through one of those touniquets against the direction of rotation. There are the Taxi's who bring people. Constantly the airport police is summon them to go. They rather take you then leaving empty so your negotion position is quite strong 😉 Going price is from 2,500-3,000฿ to Korat.
says e.g. a 60 day extension visiting Thai family (Think the visa (rest of the time)) is void then ? But also you can make a year extension if you have all requirements before all border hops are used. Possible that this only could be done in covid times ? Just ask your imm. office. Think that's the safest approach. Normally you have to do the border hops indeed. If you do the last border hop just before the visa is expired, you can almost get a year and 3 months stay.
, y'r best chance is to get a real Tourist visa (allowing 60 days in Thailand and one time extendable with 30 days) in e.g. Laos with a border run. So buying a tourist visa at the Thai embassy/consulate in vientiane or savannakhet. And then fingers crossed. Border bounce/hop (leaving Thailand, go into other country, and come back immediately) is asking for trouble with a 45 days visa exempt. Also take in account, 20,000฿ per person in cash, proof of hotel booking and onward travel out of Thailand. If this is not working, then it's time to go home for a while I guess. The covid extensions where there with reason "unable to travel home". Now almost every country is open. Good luck I would say 🤞