I believe that walls have some issues:
1. PLZ make it so u can select a row of walls and you can upgrade them all at once because it gets REALLY annoying after all the clicking.
2. Can there be a special every now and then where you can lower the costs of walls.... So like how right now there's a special that you can boost collectors for 7 days for 1 gem. Maybe next time they do a special they can lower the costs of walls for a bit.
3. And also I upgrade my stuff a lot and I can't upgrade the walls without a builder even though the builder doesn't even come out and there is no time duration on it. Could you please change that? Maybe?

