We have also trapped and relocated squirrels. Here is a website that may be helpful. It reiterates that you must take them at least 5 miles away, but preferably 10 miles.
Relocating Squirrels - Release them into the Wild
We have been using the electric plug-in pest repellant for mice, and so far it has worked. You might check to see if this would work on squirrels. I have a tendency to overdo things...if it says to use one, I use two. :-) Best of luck...the cute little guys are quite annoying.