Bonus points for grabbing a little equity or value add by targeting items on the market for a week or two and offering a little below market or finding something that needs minor value ad cosmetic touches. 

Even within depreciation there are different terms, so the 27.5 years applies to some items, shorter for others, bonus depreciation for others.

. - 1975 build date should = copper plumbing, grounded wiring, modern breaker panels- 1000sq ft shop is a nice bonus.

I will pay well and offer a holiday bonus.

When you are an investor, cash flow is what really sets the value of the property and appreciation is a bonus.  

For example, if I refinance the properties for $5,000,000 on completion, I can pay the full value of development costs plus a bonus to the developer (presumably based on the property value) for the properties in exchange for exclusive ownership.

As we discussed on the call my philosophy has always been CASHFLOW first and appreciation as a bonus (or the cherry on top). 

SO to answer your question plainly, in order to make a private lender like me feel confident in you and your investment you will need to have a property, a clear understanding of the market that property is in,  (bonus if you have recently sold comps within the past 6 months w/in 1/2 mile of the property to provide up front supporting the property value you think), a clear vision for what your investment strategy is, supporting documentation to back up your ability to pay your loan, share your experience, credit score and anything you think they might uncover, and communicate clearly as to what you are looking for from your lender.  

The seller is going to sell for a price that will basically force the buyer to raise rents. 15% is not enough to maintain the property, allow for tax and insurance increases, and make a profitReally the best you could do is tell her that you need to raise rent because of the cost, but that you will give each tenant up to 6 months to find a new place to live, or they can choose to pay the higher rent and remain there. 6 months is really generous, gives the tenants plenty of time to find something else, but doesn't squeeze you into a position where the investment could end up costing you a lot of money.

However remember that money you pull out of there is not taxed either so that’s a added bonus, however the 30year gives you a lower payment and later down the road when you refinance you can reevaluate your plan and even shorten the loan if that’s what you want.