I would like to expand and take on projects of my own, starting with home flips. 

Hi BP,I'm looking to get started wholesaling in Cleveland, OH virtually.

I am starting out as a small multi-family investor in the Boston area.

My suggestion was going to be to prorate the monthly rent for sake of starting the relationship on the right foot. 

I have started using a spreadsheet but I would like something that makes it easier to keep track of when I have sent the owners a letter or postcard etc; also to attach a picture of the property and some pdf's of county record documents.

Other than that the lender is going to lose their behind. 

I am based in Vancouver, BC and am looking to start my REI journey.

Thus, my lesson learned of walking the job with the inspector prior to purchase…or at least prior to starting the work.

I am starting a park that will end up with roughly 20-25 lots on plot of land that's roughly 20 acres (including an existing 4/2 house).

Greger   In addition to the great advice above, most lenders will require proof of funds to start the project, as you'll have to "front" the rehab funds to get started, then the property will be inspected and the rehab funds released from the lender according to a draw schedule.