I have the Roam Wild Pest Off feeder hanging from a tree in one of my runs. It is true that rodents and large birds cannot feed from it, but the sparrows can land on the feed opening and even on the little button that closes the opening when a rodent gets on it, and they feed very happily. A flock of them could empty the feeder in a day or two. I was disappointed about that and wish I could think if a way to make the "trigger button" (for lack of a better description) more sensitive to exclude sparrows as well. It looks like the birdie Berlin Airlift out there some days...
. Anyway, if you did move forward with your plans I am interested to find out how you built a coop, more specifically what auto door you used and how is it working for you? One of the reasons I am not supportive of your idea is the dependence on technology in your absence and the likelihood of tech failure, i.e., the auto door not opening/closing. I had a very negative experience with my auto door. I spent $500 on what I thought was the best auto door on the market - it had wi-fi, a predator alert, a solidly built, thick wood door with a motor that opened/closed the door, and an electronic key pad to program the door. To make a long story short, I should have just took the $500 and set it on fire instead of wasting it on such a faulty product. I had many, many problems with the door not opening up in the morning. I thank my lucky stars that I was at home to manually open the door each time it failed. I finally had my hubby remove the whole darn thing so now it is up to me to open/close their coop every day. I would love to get another auto door, especially since winter is coming. Did you have a successful outcome with your coop/auto door? 
