My friend does same but uses multi entry tourist visa. But i think with new 60 day visa expemtion it makes that kind of pointless at moment. 60 + 30 Border run then 60 + 30.
You can plan border run somewhere nice if you havent visited other parts of S.E.Asia and get cheap flights from air asia way in advance.
paying tax doesnt do it, you need work permit as well. I looked into that with citizenship and wanted register company and do that way but would have had to have 2 legal employees for a work permit for me to do overseas consultancy.