We are all unique when it comes to modesty issues. Be sure to communicate these to your therapist and most of all don't worry. Your therapist is very used to seeing bodies in all shapes and sizes. This is VERY important. These creams have a tendency to make the skin more sensitive and if you try to wax, you may end up with very sore area or even a red patch that will take days to disappear.
Some salicylic acids can upset the balance of the skin enough to cause problems durring waxing.
When in doubt, ask your esthetician or dermatologist. Try to arrange your facials and massages when you know you will have the time to enjoy them. I have seen many individuals who squeal in, heart racing, after fighting the evening traffic or the like, and it can take half of their treatment time to get settled down. I always feel like they weren't able to fully enjoy their service. Tipping is not required but is greatly appreciated by your practitioner.