ControlBuildingLevelUpMod is a gameplay modification for the game Cities: Skylines. (see http://www.citiesskylines.com/) It enables you to control your city development by preventing buildings from upgrading to a certain level. Simple select a (growable) building of your choice and click on one of the level-up progressbars and the building won't exceed over this selected lock-level. If you select a lower level than the actual level of the building it will be bulldozed.
You can open the VisualStudio-Solution file and compile the code yourself (as described here https://www.reddit.com/r/CitiesSkylinesModding/comments/2ypcl5/guide_using_visual_studio_2013_to_develop_mods/, whatever, if you are not interessted in the source code it is recommended to get the mod via SteamWorkshop (http://steamcommunity.com/sharedfiles/filedetails/?id=410535198).