Visas For Independent Consultants

[maew]

Hi, all. I'm moving to Bangkok to set up shop as an independent consultant in relief / development work; clients would be non-profit and UN agencies, and perhaps some journalism on the side. I certainly hope to get some projects in Thailand, but expect to be out and about the world (as usual). I am subletting an apartment from a friend with an empty flat there.

I have one contract already, with a grant-giving foundation to be their on-call Asia Advisor, and as they have a project in Thailand already I am quite sure I can get a multiple-entry one-year business visit visa as their official representative. They are mroe than happy to sponsor me for this, as they want me to be based in Asia for obvious reasons.

Is this enough, or do I need to get a work permit in addition if I were to take on other projects in Thailand? I have been told once to just get the one-year business visit visa (still have to leave country every 3 months, but that shouldn't be a problem given my travel schedule). I would of course prefer a work permit / legal residency as it would be helpful regarding my tax status in my home country.