However, along with this increased rental demand came more price sensitivity and compromised credit scores and/or credit "issues."

This thread is absolutely as frustrating and terrifying as it gets, DO NOT do your own structural work on ANY property if you do not know what your doing, it is STRUCTURAL, if you mess it up, which you will if you don't know what your doing, that means you will compromise the structure, there is no such thing as "ah, oh well, it was only holding the house up, no big deal". 

I guess that's something we might have to compromise on if push comes to shove.

All because of the crazy speculation near that area, you now see horrible houses costing twice as much they should, and the margin to profit after a flip is getting compromised, because there is a "limit" that who is looking to buy a house there can really afford.

Definitely just going to compromise. 

Friendly - personable, polite and professional.... not a "friend or buddy".Fair - abide by all landlord tenant laws, communicate openly and honestly, no special favors for some tenants and not others.Firm - have the backbone to hold tenants accountable, stand by your written rental agreement.Fast - swift to do maintenance and repair, swift to address tenant concerns and swift to enforce the terms of the rental agreementFlexible - take into consideration extenuating circumstances and be flexible when it is warranted, but don't let tenants manipulate you or take control.Since your grandmother chose these tenants and is compromised because of her church relationship with them, do her a favor and take on the responsibility of addressing this issue as her agent.

In an apparent compromise, the listing agent then advertised the house as having 3,750 square feet.

Removing the old shingles would come at considerable additional time and even more so expense, and per the property manager (with about 30 years or of experience) one additional layer of shingles can be added without in any way compromising the roof's integrity due to weight or any other factors.Plus a total tear off would be a factor that would further tilt the needle in favor of a capitalization requirement.   

This isn't an option either.3)  This IS an option...and maybe the best, if you can't do #4 (next)...4)  If the seller reduces their price, then buy it, but only if that reduced price falls in line with the new appraisal...not some type of compromise.  

For instance, how would you fare financially if you discovered tree roots had compromised the sewer line (~$3500 repair) and soon after your tenants stopped paying rent and by the time you evicted them and got new tenants in you endured four months of no rent payments coming in?