@Mike ******
You can get over a year out of a 6 month multi entry tourist visa plus a few land visa runs after that.
You can get 9 months out of the tourist visa then 30 days plus 30 day extension from 3 visa runs in a calendar year. That’s 15 months.
Can always do a flight to Cambodia and get another single entry tourist visa for 90 days rather than doing two land border runs.
You can also look at a one year work visa and permit under a BOI company. Or just do another ED visa.
Visa wise they cost more but when you add in a flight and other costs of going home and back, it’s probably the same price or only a bit more.