Sure you can. For a single or small iPoint environment, you may install the iPoint server, scheduler and player together on the same machine. Also in an environment of 3 players, you could install the iPoint server on 1 of the 3 player computers.
Also the iPoint scheduler application can be installed on the iPoint player computer but that would be you have to interrupt the running playlist in order to modify the playlist or the planning. Best is to install the iPoint scheduler software on the computer of the designer or maybe at the reception desk.