Genuine volunteer visas are still available, but if you were getting one of these you wouldn't be asking the question as the volunteer foundation will assist in obtaining your visa and work permit. As far as the bogus visas are concerned these are no longer available due to a crackdown by the new immigration boss. A genuine visa is 2000 baht. The bogus ones used to sell for 50,000+
Nigel Ponsonby Smallpiece. Even if were possible, there's no point. Why would anyone leave the country and return on an extension of less than 60 days, when they can come in on a 30-day exempt and extend a further 30 in-country?
There is no 6-month rule (in the days of border bouncing, it was perfectly legal and acceptable to get almost nine months from a TR multiple entry visa, plus at the monent the STV also gives nine months). Some immigration offices use it as a rule of thumb with multiple visa-exempt entries. If they are unhappy with allowing entry, they MIGHT look for something else, and that is when they enact the 20,000 baht cash rule, OR the "no onward flight" rule, so just do as Stuart has suggested and cover all bases.
Bruce Frausto. Go back briefly to your home country and come back on an STV. That way you'll get nine months without having to leave and without having to pay an agent to pay a bribe for a visa which is not quite legit.