In CA, construction costs are high, but I think outside of the state, you could hopefully get somewhere in the $150-$250/sq ft range for the vertical. 

You can add them but If you just go with what is active on furnished finder you will be right in the market range for the monthly rent and should cover the utilities + some.

@Dana Boyd our water is paid through the HOA where the cabin is located.

Because of this, I’m looking for investment opportunities that maximize my current capital and financing options.I'm considering investing in Birmingham, AL, where I’ve found several SFHs in the $30K–$40K range that I believe I could rehab for about $25K and rent for around $900/month.

Be sure to have the gas, water and sewer lines inspected as these may be dug up or collapsed - and very expensive to replace/repair.

As I posted recently on BP, some of the units that I've owned included heat and hot water in the condo fee, which increased the condo fee such their fee was in the $380 monthly range. 

Tenants stopped paying electric and water.

Plenty of houses in the 400k range that sit over 80DOM because low buyer demand, low buyer ability.

He personally screened every tenant, handled every maintenance request, and even showed up to mow the lawn at his properties when the landscapers were running late.His phone rang constantly—contractors, tenants, vendors—all needing his immediate attention.

As you mentioned, that expense range is not super helpful.