Since we already have an effort property, if I were  to schedule a task 
let's say to today using the C-s key, and I also put in  a time of 9:00 
am, is there a way for org to automatically add the effort property to 
the start time so as to calculate the end time?

Advantage with this is that if I change the effort, the end time also 
gets pushed out automatically....

Thanks,
Jose