Misinformed about Terms and Conditions

Good Day

I took a rental car through my Insurance and I told to pay R2000.00 for Access and it is Refundable, I paid in cash and I was told all the Terms and Conditions, to my surprise I got a Refund of R1950.00 when i called go enquire why i was short paid, Im been told the R50 is for admin fee which was never communicated to me by anyone, the service I received was fine, Im just don't like surprise because we plan for our money.