Batteries Plus Bulbs

First off– I want to say I have been using Batteries Plus stores for several years and when I moved to TX (McKinney) I started frequenting your store when I needed batteries. I have never had an issue until ⁷⁄₂₆.
I stopped off while I was driving by because my garage door opener (which is only 3 months old) had not been working. When I went in– the associate went over took it apart and said I needed 2 batteries and it would be an additional $ 5.99 to install. I said why– would it be an additional cost for install and he said because he had to take the back off — he did not tell me this prior to starting the work. If there is a cost — like this– your employee’s need to tell customer’s prior to starting any work. I have never had them charge me before and I will not be coming in again to your store due to this. The cost of the batteries was less than the install price. I understand that this is a cost you pass on-​however hand me the screw driver and I could have done it myself.
The associate was not friendly and acted like it was my fault for not knowing he was going to charge me for that. Nonetheless– he should have stated this prior to starting or a sign be hung where you can see it– I did not see anything either.