Married to a Chinese LAdy, and want to extend my L Visa

Hi; I married a Chinese lady last August. I changed my multiple entry F visa to a Tourist L, that expires January 15. I'd like another 6 months. I am a consultant to several US based firms, sourcing direct hardware and electronics, paid into my US account, which I draw on to live here. I changed the F to an L at the local PSB, but they said it was only good as long as the lease on our apartment, which goes month to month in January. I do not want another one year lease, as we will be moving to the US in July when our girls are out of school. What's the best way to get a 6 month, multiple entry L(Sometimes I have to go to HK).