I think you will have a problem with the sq footage formula .  

No rental v. purchase price formulas.  

Is there a formula or software you use to run your numbers to make sure this deal is viable? 

The previous owner had a formula he used to calculate the electric usage amount for each apartment based on their meter reading.I had this same concern about being considered a "utility provider" so I met with my attorney to discuss it and get his opinion if doing this is okay. 

Cash, if thats what they need (70% formula- which would then turn into wholetail/fix-n-flip).2.

I am a former student of Mark Podolsky and his Land Geek land investing system.I have since branched out to form my own free private Facebook group called "Land Motivation" which is made up of many of Mark's former and current students as well as others who are actively flipping and wholesaling land using his and other similar systems.To answer the original question of this post, I have not bought land from Mark or his Frontier Properties website but he is definitely legit and all of his students (including myself) are following his land flipping formula or some variation of it.

I'm curious if there's any tools or obvious formulas that could help me understand turner impact of property taxes in a rental property I may buy. 

For instance, a percentage of the purchase price or some other formula?

The options are numerous and wonderful.Here are some basics (a rough job here, so forgive):Columns run North and South in excel.Rows run East and West.Cell - an individual box where you can enter data.To compute items, you need to align a column that is an item (such as a window) with a row that is a Cost or Number/Quantity (such as number of windows or cost of windows).Example:To compute 15 windows @ $10 each, you use a formula in the cell you want this information to appear.

We have a formula we use to determine equity splits that values debt dollars at 70% of equity dollars based on the project's overall capitalization.