Some questions are:
Will I earn the same or more net profit from the proposed new market than I would from investing the same additional time and effort in my existing market?
Will the new market increase my cash or % return on my total business investment?
Is there another new market where my investment would earn the same or better return for the same or lower risk?
Will investing in the new market draw resources away from my current market? If so, should I factor in a loss of return from my existing market until the new market is established?