Labor is cheaper down there, USD $2.50 per hour, which is normal rate. 

No interest rate to mess with.

I do relatively well in my day job by today's standards but my hourly rate for self managing is closer to that of a surgeon. 

Interest rates NEVER matter and you can make money all the time.

It gets complicated if you use a HELOC towards two separate projects as you would need to pro-rate the interest across the two projects.However, the answer would be yes, they would be deductible.

For example, if $100 buys a basket of goods today, in 10 years, with a 5% average inflation rate, you'll need $162 to buy the same items.

You can find higher ROI (on paper) here and probably in other cities…but the probability of actually collecting rent significantly decreases.

Rate is 4%.

I understand that the investment or time and energy is required and correlates with success rate.

Due to increased rates i did not refi so i did not get opportunity to see how an appraiser valued the half bathroom but the comps with same bathroom count had crazy valuation for the additional half bathroom.Taking under utilized space like a work area to add a br where the added br does not put you above the normal for the area can add value.Similar if a neighborhood is virtually all 3 br and 4 br properties and you find a 2 BR, it could be a value add to add the bedroom via new construction.