Rent fluctuate with market, deposit is minimum amount of anticipatated repairs/damage.

Their income obviously fluctuates slightly from month to month, but over the course of the year they average roughly 2x what they could otherwise rent it out as a LTR. 

The value of one apartment unit that we own, for example, fluctuated between $1.2 million to $3.5 million in a matter of 15 years or so.

@Sela FlynnIts very difficult to time real estate price fluctuation given its illiquidity and long cycle times. 

It is similar to a home loan, when a home is paid off, the home still grows with inflation and market fluctuations.  

An excel spreadsheet is likely your best option, of course the spreadsheet pricing for individual tasks would need to be adjusted accordingly to price fluctuations over time.

IMO the Rochester investor market generally sees less fluctuation than the primary market.

This insulates me to some degree from short term market fluctuations and gives me multiple exit strategies to sale for profit at any time should I need or choose to.

Plus, the holding costs can fluctuate dramatically depending on what kind of rates and terms you have on your borrowed funds and how fast you can flip it.If you wanted to wholesale the deal, you can use your standard realtor forms (provided by an agent or perhaps title/escrow company) or can have docs drafted by your attorney.

Some of those neighborhoods fluctuate from good to bad blocks and hence things can go from A to D grade fairly quick.