They make you go out with a blow up type vest which is no charge. I am not sure how much the fins are, but I didn't use any and it was just fine. I bought my kids their own gear at Costco and thought I would just rent mine. My DD (age 7, but size of a 9 year old) didn't want to go snorkeling so I decided to see if her mask would fit me. It worked great and I was so glad I didn't spend the $35 to rent the equipment (especially because DS and I only snorkeled for about 1/2 hour). Good luck and enjoy yourself.