As you know, I am very much in favor of only using point of sale systems that allow you to pick, choose, and change which company handles your merchant services for debit and credit card processing. As we all know how competitive merchant services companies can be, the worst thing we can do is lock ourselves in to a long term contract or commitment where our rates can be raised.
That being said, it is likely that changing who handles your merchant services may involve a fee and a service call to change the information in your point of sale software - plus you want to test the new settings to make sure that everything is functioning correctly.
Most point of sale companies charge $250 to $800 to perform a "change of service" related to changing the settings in your point of sale system so you can switch/change merchant services companies. I've found that it never hurts to ask the company that you are switching to for merchant services to cover that fee via a credit or series of monthly credits - just be sure to get in writing!
That way, you can make sure that you are always paying the lowest fees for debit and credit card processing.
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