If you are unsatisfied with your current lender and the services they provide, don't stay because of the hassle of a change. There is currently a lot of competition for your business and your financial wellbeing is a priority.
We are in an ever changing market - if you have signed a home loan deal within two years, you should not look at refinancing for a least another year or so. Be aware of when your term is up or coming to an end, then begin to research potential lenders at that time and not before.
Refinance with the lowest interest rate - Finding the lowest home loan interest rate is only a small part of the refinancing game. Look at comparison rates and interest rates combined with fees you'll pay over the life of the loan. You may want a package that offers offset accounts, lines of credit or options that better suit your lifestyle and goals, even if these have slightly higher interest rates.
Applications with different lenders - The more applications submitted, means the more often a lender or broker does a credit check. Don't approve for a credit check to be completed until you're sure you are going to proceed with an offer. Credit checks conducted more often can harm your credit history and may lead to that application being declined, or less than ideal interest rates offered.
Don't fall for "honeymoon" rates - Due to the competitive market, honeymoon rates can often rise to bigger rates after the honeymoon period and can end up costing a lot more overall.
The purpose of refinancing is to reduce interest and possibly the term of the loan, short term benefits are not worth the risk, cost and trouble in the long run.