How many myanmar business visa do u have, if you already have 3 visa then you can apply business visa for 90 days without going out side of myanmar, 40 days b4 expire the current visa you can apply for 6 month visa and after that 1 year visa, in long term visa you will get 2 option in that multi entry or single entry . . . . Multi entry will be costlier then single entry . . For more information you can search myanmar visa consultant in facebook and before proceeding please visit their office first, hope you will get your answer.