Hey Mac – you are lucky as shopify has alot of options – the biggest thing (as others have mentioned) is to find out what process you want for your users – we see alot of people add in things to do one particular function where some of the apps for the VIPs etc can also do alot of other things inside the website as well. Some people who come to us with existing websites have installed a large range of apps and they all cross over – so we usually spend the time working through this exact process – to find out their business processes so we can fit the right app to their internal requirements – so, my advice would be to figure out the process that you want and how that works with any internal systems you have in place and then from there you can search the list of available apps and research which best fits your needs 🙂