Any time!! I'm glad that you are finding them helpful. Feel free to ask anything - it's nice to be able to chat with GSP brides. In terms of vendor fees for your make up artist, it would probably be cheaper to pay for a day pass which is $95. You can just say that it is a friend that is coming in for the wedding.
We brought in our own make up artists and photographers but since they were staying at the hotel there were no problems in terms of vendor fees. There are two Spas, one in the Platinum Yucatan and one at the GSP, I had a great experience at the Platinum Yucatan Spa. We also had our couples massage there which was included with our wedding package and it was epic. So relaxing.
One thing, a little tip, if you are getting your hair done at the salon, it does include a hair trial. The spa employees were so friendly and made sure to inform me. For some reason it's not really advertised but if you book a wedding hair appointment you get a trial.
I ended up making my appointments on the first day that we arrived. I wanted to check out the Spa and salon first. They also have a nice little area for all the bridesmaids to get ready and do their own makeup if they so wish to do that. My room was super big, so everyone gathered there, but it is a nice option to have everyone in that little bridal room too.