Yes you can host your server which has been stated in many other threads. Basically if you have it open the Server config tool or if not open the serverconfig.cfg with notepad or something and edit the parts that don't have # next to them. Then save that file once you've finished and open MTAServer.exe, then you have it. If you want admin just open the admin panel and type the ip of your computer, then the port you set admin ort to be, then the password you set. Hope it works