Unfortunately, you're unlikely to find something that does what you want without a more complex accounting methodology in place.  

An appraisal in essence is an opinion of market value based on supportable data compiled by a trained professional.The scope of work and methodology will depend on the type of property and the lenders requirements.

Have been searching for this methodology for a long time with little success. 

Keep up the great methodology.

Home Flip Characteristics for 2018Average time: Homes flipped in 2018 took an average of 180 days to complete, down from 181 days in 2017.Square footage: The average square footage of homes flipped in the fourth quarter was 1,408, the smallest average square footage on record for CoreLogic’s report, dating back to the first quarter of 2005.Financing: Thirty-six percent of all homes flipped in the fourth quarter were financed, down from 39.5 percent a year https://www.attomdata.com/news...Report methodology The average gross flipping profit is the difference between the purchase price and the flipped price (not including rehab costs and other expenses incurred, which flipping veterans estimate typically run between 20 percent and 33 percent of the property’s after repair value).

Generally, the allocation is made based on square footage, or acreage, but other methodologies are possible.You would not need to acquire another property that is either a duplex or a two on one in order to qualify for 1031 Exchange treatment.

Their credit scores are in the mid 800s, which in a way is a bit of an indictment of credit score methodology - they only have one credit item, and not much history to go on.

A methodology for analyzing an STR.

Using this methodology, Davis and Palumbo calculated land values for 46 U.S. metro areas, which can be found at the website for the Lincoln Institute for Land Policy.[15]When I was looking at a lot of property tax records in Southern California in 1990, I noticed the hottest markets started at 50% land value for assessed valuation and ranging up to 80% land value.  

These values are all derived using different methodologies and they are not related to each other.