Water issues are the most common. 

A common example is Cleveland.

IE its common in so many areas that the 500k home in Wis sits on a 75k or 100k lot and 300 to 400k is the cost to construct say at 150 to 200 a foot..

Just want to start setting up as if it were. so far i have thought about creating 7 accounts.1) all rental income account 2) account where common utilities and mortgage will be billed3)maintence/capex expenses4)vacancy expense5)management expense (to put the units up for rent)6) property taxes 7)cashflow am i missing anything? 

I will give you the common-sense answer below, but this is California, where common sense doesn't exist.A mandatory evacuation is outside of your control, so you shouldn't suffer financially because of it.

Is a shared bathroom common or should we add more?

I feel this gives me the flexibility to find the right solution for my client and not just sell what my bank offers.I'll also throw in my 2 cents on common differences I've seen in my career:CDFIs - Because of their subsidized financing structure, they have the ability to be a low cost lender (and sometimes provide grants).

@Phil SheltonYou would need a civil engineer to provide a drawing to get submitted to zoning and get a permit if it passes zoning is most common This also depends on the road - if it’s a state road forget it as it will take a year to get approved and cost a fortune - if it’s a local road process not as cumbersome but don’t expect this to happen quicklyIn some instances you may have to prepare sight distances etc to make sure it’s safe to add a curb cut

I have one property in an area going down hill and this is common. 

In real estate, blunt honesty often protects people from common pitfalls or predatory advice that oversimplifies the challenges of investing.