Building a 100,000 sq ft Office Space

[Nathan Milch]

I'm in a Masters course where I need to do a Front door and Back door analysis for building a 100,000 sq ft office building in Florida.  The following criteria was given to me:

• 100,000 square foot office building.
• Land $600,000/ Acre
• FAR: 0.33 per acre
• Construction costs (buildings only) $150/ square foot
• Land and infrastructure improvements $25,000/ acre
• Fees of $20 per square foot
• Soft costs 20% of all costs excluding land
• LTV of 80%
• Mortgage 25 years 6%
• Debt coverage 1.25
• Needed return 10%

---Front door Analysis. What rents are required? This model is designed to

calculate the rent needed to provide an adequate return to support a

specified development or concept. . This approach establishes the rental

thresholds for for the various project components or activities

---Back door Analysis. What does the markets say? This model relates

income to the costs of development. The model begins with the most

likely tenant or user, and establishes budget that can be reasonably

allocated to real estate, and subsequently justified based on expenses

and needed returns.

How do I figure out how much land I need?

Can Anyone help with the calculations?  

I'm getting that I need to charge $17.01 for rent through the backdoor approach.. but struggling with the Front door calculations.