Acquiring mini-storage units. Help on analyzing this deal.

[Jay Helms]

Afternoon BiggerPockets Tribe! I have a 38 unit mini-storage building under contract. It is a one 2800 sq ft building facility (built in 2004) on approx. 1 acre of land. With the opportunity to build more buildings and/or offer Boat/RV storage. I had a mini-storage friend review the below with me and he essentially told me the business wasn't worth anything, that I should just offer to buy the land at market value. Realizing that is only one opinion and encourage me to prove him wrong, I want to gain additional insight for guys who have experience in self-storage. My wife and I plan to self manage. 

• Self Storage Purchase Price: $169k

Current: 

• Annual Income: $15,180
• Annual Expenses: $3,487
  • Insurance: $1,636
  • Property Taxes: $1,177
  • Electricity: $762
• NOI: $11,693

Year 1 Pro Forma:

• Annual Income: $17,460
• Annual Expenses: $4,720
  • Insurance: $1,220
  • Property Taxes: $1,375
  • Electricity: $762
  • Grounds Maintenance: $1,400
• NOI: $12,740

38 Unit Breakdown (currently under market rents by $2-8/unit). 

Current Rents: 

• (20)  10x10 @ $45
• (14)  10x5 @ $25
• (4)     5x5 @ $15

What do you think about this deal? What expenses am I missing?