Hi @mamasaurus - glad to hear you are planning family camping trips! The good news on roof racks and cargo boxes is that our local stores can help you choose a set up pretty easily and we can take care of the installation too! I would start by making a list of all the gear you probably want to carry in the cargo top box; think about upcoming trips like you mentioned (sleeping bags, coolers) and also consider future use (any chance you will plan on carrying ski's or traveling accross the country?). Having an idea of how much gear you want to hold is really the first big question to solve. This article is pretty exhaustive but it can be great reading material and offers some concepts to consider too. Once you have an idea about gear load, I would head into your local REI and the team can show you a few options in person in the size range you'll need as well as compare brands with you and schedule in install when you are ready. Happy camping! 

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