If I were in your shoes, I'd offer the friend debt only... a 6% loan with terms as long as your friend can handle.

while I normally never offer up my own services, I realize what you are seeking appears to be very time sensitive and your needs require a unique skill set that is not on every block.Having said that, I am a Nationally Certified Forensic Accountant, a Licensed CPA, I am a Licensed Florida Real Estate Agent, an avid real estate investor that owns 26 different commercial and residential properties, a Nationally Certified Business Valuator, have valued hotels and storage facilities in litigation cases several times, was a licensed Mediator for the first 11 years of my career (mediated over 3000 cases), Certified in Financial Forensics by the AICPA, a Personal Financial Planner and have a Doctorate Degree in Jurisprudence (law degree).  

I tried to give the pros and cons of storage.  

And I was wondering what everyone's thoughts were on obtaining storage unit facility?

Tenants agree to pay the rent on the first day of each month.Tenants agree to be jointly and severally responsible for the lease and rent.Tenants agree to put trash & recyclables in containers provided by the landlord, to place on curb on day designated by city, and to abide by ordinances in regards to lids on cans, proper trash storage, etc.Tenants agree to not smoke in the building or apartment.

Hello,We recently rented a warehouse space for storage purposes.  

I wouldn't hang my hat on my friend, in your shoes. 

I am a real estate broker here in Fresno, CA and I was in your shoes looking for full funding from a lender, it's not going to happen, they want you to have some skin in the game meaning you would need to put down anywhere from 20%-35% and they will fund rest.

.- The house has a detached 2 floor storage unit that could very well be rehabilited into a studio or 1 bedroom.

You may be better off spending extra time going through 10 years of shoe boxes of receipts to maximize your expenses and capital improvement deductions.