My friend has trying to get some clarity as to whether working visas can be extended by 30 days and I figured this would be a good place to get some advice/experiences etc.

Thanks in advance.

There is no work visa and visas are not extended.

If a person has a 90 day non-b visa entry it cannot be extended for 30 days. It is the same for an extension of stay based upon working. The only extension possible is 7 days to leave the country.

Thanks ubonjoe you're a fountain of knowledge as always. My friend must have the non-B.