Online resource/spreadsheet for projecting future income?

[Tina Peters]

I am a long time investor of residential single and multi-family housing, primarily buy and holds.

I've played around with creating a spreadsheet to project income over varied periods of time as well as plot out when each property will be paid off.  While it's ok, it's lacking.  Is anyone familiar with a BP resource or have a spreadsheet you'd be willing to share?  Thanks in advance!