Even 600k loan at 10% interest costs $165 a day.

Or if you want a lower monthly payment, then do the 20% down.You can also negotiate credits with the sellers to use towards your closing costs or rate buy down.

In southern CA, even garage conversion ADU additions are typically costing more than the value added.  

.: Quote from @Cameron Moore: Another example: the average roof in DFW is replaced every 6 years and the average cost is $40k.

This designation doesn’t cost extra or give the manager access to insurance payouts but ensures you and the property manager are aligned during incidents, such as tenant lawsuits or insurance claims.

If a person has RCV or ACV policy makes a huge difference, than question of what coverage level people had and if they had policy add-on's that cover cost over-runs and all that fun stuff, not to mention contents. 

It's the cash you put in that's your cost for the property. 

Maybe that is gross profit when you sell it, but what about the cost to build it?  

Quote from @Devin James: Im currently learning this lesson with New Builds that have taken twice as long to complete than anticipated.....Finishing a Real Estate project ASAP is critical because...1) Holding Costs add up quickly- Loan Interest- Property Taxes- Insurance2) Investor Capital- Our financial projections are dependent on how fast we can turn our investors capital.

Now, you are asking can you use a Gap/Transactional funder for the downpayment and closing costs?