Estimated Costs to Build Self Storage Facility

[Kyle Bryant]

My family owns about 3 acres in a semi-rural part of Montgomery County, Texas. We recently found out that the new "Aggie Super Highway" from Houston to College Station will have frontage on our property. So we have been considering building a self storage facility on the lot in anticipation of the future growth. Aside from market considerations, I have a few questions:

-How many rentable square feet can I reasonably fit onto 3 acres? About how many units?

-What is the estimated cost to build a decent facility in that part of Texas (cost per s.f. or similar)?

-What is a reasonable profit margin per unit per month (or something similar) to expect for self storage units? 

Keep in mind we already own the land, but there's nothing on it. We'd be starting from scratch, and we would want to use a management company. This would be for stable cashflow. I know self storage is all the rage right now, but I haven't seen much on new construction of storage. Thanks in advance for any guidance!