However, I've heard many mixed opinions from different professionals.

If your loan comes from your builder or if the construction loan comes from your lender (both will have different requirements) and there is a difference between a "one time close" construction loan and a "construction to permanent" loan. 

I've driven by many times in the past, it looks like some differed maintenance. 

You will convert from normal income (rental) to interest income which is taxed differently. 

Simplifying the processes, laws and regulations into a few basic scenarios when in reality each state has a wildly different set of rules, laws and procedures and each county and often municipality has their unique set of procedures within the state3.

Each Church is different with respect to design but they are generally more expensive to renovate than some other structure types that may lend themselves better to a conversion.

There is not a specific type of client that all lenders desire since every one has a different credit box.

Looking back would you do it differently/change the sequence of which account to draw from first? 

I know Detroit is different than Grand Rapids, but that my only data point close to Grand Rapids right now.

@Joseph Turner The funds seasoning period (ie the amount of time the HELOC funds are in your liquid accessible bank account) is different than the ownership seasoning of the property.