There has been a fair amount of discussion regarding using OSX Server vs. Calendar and Contacts Server when the latter is all one really needs. However, know one has really addressed whether there is any significant savings of system resources by installing just Calendar and Contacts Server. I have tried both options on a retired MBP (barely Mavericks ready) but the results are hard to interpret. OSX Server appears to use a good deal more memory; however, with Mavericks' new memory management, the results of Activity Monitor are hard to interpret. Both options seem to require a surprising number of processes. I did not find the cost of OSX Server unreasonable, but the quality of the documentation made it only marginally easier to setup. Among other complaints, there are critical help issues that are not accessible by simply choosing "Server Help" from the Help menu, which was my first impulse as a newbie. Instead these help items are only availabe from inconspicuous links (ie. barely look like links) in the setup panels of the individual servers. Neither option is sufficiently documented for a new user to setup without dredging the net for third-party tips. On the CalendarServer site you can't even determine what the preferred stable release is or whether any release is more appropriate for a particular OS version. Given the above, resource usage is the deciding factor for me. I am hoping to have this question resolved before my long-over-due, new Mac Pro arrives and I am forced by Mavericks to set this up. Thanks, jb