Ron webber

I understand I have to leave Thailand, without obtaining a re entry permit, to cancel my current OA visa. I was considering either going to Lao or Cambodia, border runs by land, and returning almost immediaetly to Thailand. If I go via the border run to Cambodia, how long a visa will I be given on reentry to Thailand (not going to go to Thai embassy there, just in and out of the place) Likewise if I go to Lao, do I need to get a tourist visa from Thai embassy there, or can I just get 30 day visa on arrival on re entry to Thailand. I understand I need at least a 30 day visa on coming back, to allow time to apply here for an O visa. I remembere some years ago I did a border run to Cambodia, and was only given a 7 day visa on reentering Thai, I was told that was because I was a land, not air, traveller... Unable to obtain any insurance due to pre existing health conditions, and sure am tired of making "arrangements" with local I.O. officer.