There's a VORACIOUS appetite for these loans.  

BRRRR is common in commercial and your existing lender will need more of an appetite for a refinance if they know that they are going to loose the loan.Fannie, Freddie, and some local/regional banks actually have a supplemental loan feature that facilitates a BRRRR...the original loan stays in place and you get a supplemental loan when the property has been re-positioned, rents raised, and stabilized.There are also construction/perm loans where rehab is financed during the IO construction period and then the loan starts amortizing later. 

We had a mandate that required all new residential homes in my town to be built with fire suppression sprinkler systems.

Its all about your appetite for risk and your goals. 

But if I suppress rehab cost, then I may not be able to get ARV up to the target price range. 

As far as Self Storage goes, the best piece of advice I can give is ask the bank what their appetite for self storage is, and when they answer, "We love self storage" ask them how many self storage deals they've closed on in the last year.

In addition, it would be helpful to talk to the exiting residents and see how much appetite there is for them to own and to get a sense for their financial strength.Hope this helps.

My objective is to build a nest egg that I won't touch for 20 years or so, and I have a pretty small appetite for risk in this portfolio. 

@Bill Brandt  Appraisers are trying their hardest to keep this market suppressed and under control..  

Lastly, if you do find even minimal cash flow in Auckland, do you have appetite to invest here for the cash flow & appreciation, or would you still go for cash flow properties in TN?