Here is an article that goes into DTI and what factors influence it.However, the fastest way to get your questions answered, and/or to find out how much you qualify for, would be to speak with a lender.

The list includes:Demand in the market & factors that influence said demandLocation of the propertyPhysical condition of the propertyIts proximity to youEach of those has many sub-factors.

How are you boosting the value?

I’ve been influenced by Dave Ramsey and paid off mine.

I wanted to see If I did any capital expenditures how much that would influence my bottom line. 

.- Its also my understanding, when working with the right lender and appraiser they can include the income of the property for the refi appraisal. boosting what you may be able to pull out on a cash out refi-  I am familiar with STR property management companies that will guarantee to increase your net while earning their split. helping reduce your personal labor.-  Another option you haven't mention...

Also, if you can add in extra bedrooms or bathrooms as part of the reno process that will boost ARV and rent rate.  

This house has no equity and is in a volatile market that is heavily influenced by oil and gas prices in west Texas.

I’ve done research and found out that things like paying off credit cards and paying rent on time can boost it.

This would by far be our largest client and would heavily influence the growth of our business.