There are some exceptions to the rule if you "actively participate" or "materially participate" in the real estate investment. 

For the most part though,  they only have to approve exterior changes such as paint color, fences, roofing material.  

Just because something doesn't need a lot of material and labor doesn't mean you can't get it at a great price.

And is it still smarter to use the nicer materials and go ahead and make the kitchens a bit nicer with new cabinets rather than salvaging the existing cabinets?

Edwin Gachinga It cost me roughly $3,000 for labor and material.

Do you have official certs on this material?

You also have to pay for all the materials or give him rent credit for them. 

For example, you say that your rehave will be 70k, well you may need to list out all of the materials and labor assumptions that go into that number. 

update: in addition to the books above, Rick Villani and Michael Corbett have excellent material

Savings is important - 6 months of living plus expenses to start up your business (licensing, MLS fees, professional orgs, E&O insurance, basic materials like business cards and signs, plus marketing you plan to do) seems a reasonable estimate.