Dear sir
I have gone through your requirement and understand your points, have interest in it.
I have much experiences in mobile development with Xamarin.
I can work full time, can start work right now and do my best until you satisfy.
I can also do UI design myself, so no need worry even you don't have UI design.
I will show you daily advance everyday and provide maintain service after develop done.
I developed and uploaded almost 60+ apps in store and can share some links via chat.
Hope to discuss more via chat