most of the time its easier just researching online and going direct to the bank to do the application but brokers are good to go through all the fees and charges and features and services a particular bank offers, also depends on P+I or IO loans and some banks are now offering cheaper rates to LVRs under 70%
you will have a repayment adjustment if you are currently on a fixed rate otherwise shouldn't be a break fee- there will be some kind of discharge fee usually around the $300 mark
the incoming bank should offer some incentive for you - there's a few offering $2000 rebates (big 4 as well) which should cover all your costs to move.
also keep in mind there has been a butt load of changes since the RC so dont be surprised if you can no longer pass the serviceability tests at some
you can get 4% for 2 year fixed at the majors for investment P+I - will get cheaper at your 2nd and 3rd tier banks
