You may ask if he would provide seller financing in order to help you get this off the ground. It could look like this:
1. You pay 10% down and balance to be carried at 6% interest only monthly for 1 year.
2. When you get a construction loan for your rehab costs, he agrees to subordinate his note if you pay down an additional 15% (which will come out of your rehab loan) and then increase his interest only interest rate to 7.5% for two years. This allows you to get all rehab money from an institutional lender, do the rehab, rent the property out, stabilize and then refi into a long term loan and pay off the first and second while minimizing your out of pocket expense. You will have to play with the numbers, visit with an appraiser or someone that has worked in your area to see how the final value plays out.
Each time that you change the use of a piece of property, you will increase the value.
That increase will give you the equity you need and the time will give you the ability to find a take out loan. Most construction lenders will want to know that you can get a perm loan when the deal is done (you will need to see what the Perm lender wants to see and how the income will qualify you for the loan).
Best results to you.
Duke