[pokeefe45@aol.com]

I believe I paid $900 for the 4 retractable screen doors-but the tracks were existing-I THINK it was $1,200 if the tracks were needed as well. I used 'Thumper's' as well (Like the other poster said-googling Thumper's Retractable Screen Doors' will take you to the website).
I can't imagine having a motorized one-the manual retractable one allows me to get in and out quickly and actually encourages idly meandering around my front yard to chase anoles, or water plants etc. Like it's been said already-you keep the track swept,cleaned and oiled very occasionally and you've got yourself a great product that will last years.