Lenders will most likely require all these docs.

from everyone in your current network and make sure that total amount if 150% or more than the money required to close.There are a lot of other factors to consider but the above it a good start.

You correctly pointed out real estate investing requires liquidity/cash reserves.

And also proof that tenants were not harassed when they left is a requirement to the conversion.

I understand this requirement is in the Texas Property Code, but I want to confirm it applies to student housing. 

I want a template that will automatically give me all the equations and include both the purchase, a cashout refinance with a new mortgage balance and % along with recording all the rents and expenses. 

You should be able to get maybe 3 properties out of that, and the cash flow from them should start replenishing that savings.Aggressive house-hackingHouse hacking will be a quicker path but requires you live with others.

I am strongly considering cashing out my 401K in order to be able to afford the 20% down payment that is required on my next duplex. 

This requirement applies regardless of the property's purchase date, even if acquired before the implementation of this ordinance.

My position would be to only allow the new resident if they meet your requirement but NEVER let the one moving out off of the lease until all of them are gone.