If this is negative, its a net rental lossIf net rental income is positive, DTI = (income  + net rental income) /debtif you have a rental loss, DTI = (income)/(debt + net rental loss)IDK if every bank does it like this or of if there are variations. 

These are complex questions with answers subject to variation.

There is no way I can collect a set dollar amount each month to cover these numerous variations.

You need to know your score for all three.Different creditors pull from different agencies depending on where their headquarters are located.I have seen point variations in the hundreds of difference per agency before.The reason is people have similar names etc. and info gets reported incorrectly or to the wrong file.

While I expected some variation, that amazed me.In looking further, here's what I found out... the lowest simply insured me for the appraised value (I told them $85k even though I was paying $72k)... the next insured at $100k stating that was their minimum... above that was a quote at $160k because that was their estimated replacement cost on the property... still another had an estimated replacement cost of $200k!

There is quite a bit of variation in the designs you can see from this house and in the neighborhood in general.

The lease/option (it's a variation) seems to do all it's needed for this.

Probably the best part about it has been that it produces variations in the letters (so it isn't a dead-giveaway that the letters AREN'T actually hand written).

I wouldn't have a problem doing it at all, but I certainly understand those who don't have sufficient experience with off center deals would not want to get involved.As each state began putting out their version of the SAFE Act I didn't keep up with all the variations, so it's best to check in your state law.From my last reading of the federal outlines, it appeared to me that the MLO was going to be about the same degree of difficulty as a real estate broker's license.....not much.

I have seen wide price variations depending on the provider.