if you care about your broker, then don't,

if you refi within 6 month, most likely your broker will have to payback the commission they earn, or at least part of it. wait a year if you use the same broker, 6 month if different broker.

one other point you need to consider is if you have to pay 7k upfront, to save $150 a month, means you have to live there at least 5 years to break even.