I've seen a video on youtube froom "Commercial Property Advisors" saying that it is actually better to buy a 5+ until as opposed to a 4 unit building because then the loan is commercial and the property cash flows factor into the evaluation of the property in underwriting (in addition to you still being checked out for income, assets, debt, etc.), whereas with residential, you can qualify for residential on just your income and assets alone, no evaluation of the property.  

We currently do factor in 10% in our budgets for surprises.

I am currently integrating providing skills and land to people who are interested in living off grid so I'm fine there.

I told the new buyers that this was one factor that said that this was a good property to own. 

Just as an example on one of them...they way over improved the property for the price point, and they also did not factor in the fact that this property did not have a yard...and Frederick is a very dog friendly city...so not having that yard really brought down the value.

When the property is evaluated for tax purposes it is then multiplied against this factor to get the assessed value.

Depends on your state but most states treat mobile homes as personal property, titled like a car, this depending on a number of factors.

And, owner-occupants who want to live in one side of the duplex are also bidding up these properties.Consider the following factors that can make a big difference in your ROI:- What will non-homestead taxes cost you?  

Let me tell you its like pulling teeth trying to get a rate and fee quote (yes I totally understand that rates change and it is dependent on a variety of asset factors) I did find one small credit union that gave me 5.25% 80 LTV 25 year amortization, 5 year ARM, and only 0.5 point fee - problem is they are restricted to certain states.

This will be a big factor in getting a cash out refiWhat bank are you working with.