Maybe an easy question! I am planning some regular trips to Thailand to investigate moving my business there. I will be coming to Bangkok ever other weekend for several months.  My question is - I will get my passport stamped on entry for a 30 day tourist visa.  If I leave Thailand and return within that 30 day period, do I need to get a re-entry visa on my return within that 30 day period? Or do I just point out my existing visa stamp to immigration? (Or do I do nothing and get a new 30 day stamp?). What if my return visit of a few days exceeds the cut-off date of my existing 30 day visa?

Any advice needed and please don't think I'm mad to travel halfway round the world to visit Thailand just for the weekend!!

cheers - Simon

You do nothing, you will get 30 new fresh days on each arrival.

You might consider getting a Multiple Entry Non-Immigrant visa instead of this 30 days as tourist... The imm. might consider you doing business or working, and you are not allowed to do that as tourist.