Be aware that in thailand a visa is no garanty at all , the officer at the immigration point can always give you a hard time if he thinks to do do , and they have the authority over the visa and entry
I do not have that problem , as i work so i have my visa , i can move freely in and out of thailand when ever i want , 1 visa trip per year , and 3 border runs , i pay tax , and everyone is happy and leaves me alone since about 15 years now , visa cost in total about 60 000 thb
Maybe just do the normal tripple 60 plus borderjojo and immi-extension so he will be good for one year easy just swap points of entry or immi each time
Fly out to kl ,hk,sin,mum,pp,yg,kb be at the embassy on time to drop , check for close + holidays online, check the correct application and copies and paper , pick up next day at time and fly home , 1 night , aprox tripcost 20.000