Welcome. In regards to buying guides...just do a google search for BMW f15 X5 ordering and pricing guide (type in the year you’re looking for). This will give you info as to what was standard and included in the option packages. Things like the driving assistant pkgs were in constant changes as each model year ticked off...so a 2014 driver assist pkg will not be the same as what was offered in a 2018. There’s also multiple trim levels and interior/exterior “experience” pkgs which can give the vehicle multiple looks/options.
There are also some really good videos on YouTube that cover when the f15 first debuted...and some of the things to look out for and issues that came to light after a few years of being on the market.
Good luck in your search. You may also find other sites that may be more active with day to day f15 banter. So be open to being dedicated to more than one site.
