If she went to Assisted Living - I can help you but it's only KS Specific - each state is different but I'm guessing some of the guidelines carry across states in regards to how she will pay for the ALF and eligibility for Medicaid and Home and Community Based Services (which is a medicaid program that would help pay for ALF)Anyways in KS - in for someone to qualify for HCBS/Medicaid to help pay for their care either in the  home or assisted living - you need to have less than $2k in assets - and consistently less than $2k in the bank - there is also something called a 5 year lookback period - I do not 100% understand how the lookback period works but will soon enough.So - as far as the assets are concerned - if your friends mother has the house and any savings there is no way the govt will be paying for most of her stay in ALF - and I also think it would be difficult to house her in an ALF facility for $3k per month - can be done but tough - Due to no estate planning the family needs to decide on what they are going to do - they will either need to sell the house now and just pay her money down at the private pay rate in a facility until she "runs out of money" then apply for Medicaid and go from there or see if the strategy of renting the house with her present income will be enough to cover the facility she's staying at.Individually the systems are simple however there are so many moving parts to Medicaid HCBS I've discovered in my time as owner of a facility I can 100% understand the families frustrations. 

My question is, with all the moving parts: financing, permits, zoning, platting, building - how would you start thinking about and making sure all of the costs are taken care of and you’re not missing anything?

As far as formulas, at the end of the day, all you should care about is Cap rate or NOI.

You usually have to have some skin in the property in order for them to lend to you.

Who really cares, so long as it gets properly remedied. 

In general, the federal government doesn't care HOW you borrowed the money, they care what the borrowed money was used for.

Rents are already outpacing wages,  so be careful of speculating future rent increases in the near term. 

My wife is in health care too.

We add in insurance, property management, CapEx, maintenance/repairs, vacancy and any other potential expenses based on the property (refuse, water, etc. fo MF and lawn care/pest control for SFR).

It's a wonderful business, so long as we remember it is a BUSINESS and needs our careful attention and supervision.