All I know is that you "MUST" get a long term VISA at Orchard
and that is very straight forward. Fill up the form and you get it
the next working day. It is a single entry long term Visa.
Over in Bangkok, I understand that there are "agents" that can help
you get a multiple entry VISA. Seriously I do not know what the
conditions for multiple entry Visa are as but mine was for
employment so it was no problem since I had work permit.