Do you have a preferred method and format for keeping track of all of that information?  

I am looking for either flips or rentals that I can use the BRRRR method.

I broker my HELOCs to TCF bank specifically because they will accept Fannie and Freddie's standard methods of calculating DTI (which your local credit union obviously is not) instead of re-inventing the wheel, with the only deviation being that they will calculate their own debt obligation more conservatively (which makes sense given that it's an interest only product in 2nd lien position). 

I would like to do this method, but have 3 little kids and moving that often sounds horrible, even though it dies make me clean out all the stuff I don't need!

Then I will use the BRRRR method (Buy, Rehab, Refinance, Rent out, Repeat) to continue building my portfolio.

Often it is just trim, door frames and such that are lead.

There are other methods available for low or no down, but a bank isn't one of them. :)  

If you start doing work by taking off trim or demoing a part of a room the plaster tends to crumble.

Did anybody finance their first property utilizing that method?

Little extras when I am servicing a unit anyway (like a new toilet seat or faucet or porch light unexpected), greeting cards at holidays, common areas decorated for the season or trimming a tree, weeding, etc. without being asked.