Because of the variables of types of homes and costs to bring them in like you mentioned, I left them off the report. 

The price of the property, what you can charge, your total expenses, all are variables.  

I need to do some research on all the variables so I can buy right.

They are too many variables at stake to be able to have a general pricing rule for land, regardless of location.

Lastly, in effect, solar turns a variable cost (electricity) into a fixed cost which I'm paying up front.For those of you interested in going solar in Arizona, I found this article which you might consider.

The property has no mortgage, has a Zillow value of $135,000, and I have a 807 FICO score but could only get $74,000The appraisal will cost roughly $450 and the terms are a fixed 4.50% for 3 years and then a variable 1/4 point below prime after that. 

Thanks Charles and Justin.What are the variables determining the fee rate?

I would not proceed with the purchase because the after rehab value may be affected by the rent charged for the lot, this is a variable you do not control; +$75 - $100 in lot rent would have a dramatic impact on your value and the amount of money that the bank would give you when you to try to refinance.  

Typically, the lower this number, the better (underpriced, cheaper etc.).The price-to-earnings ratio is structurally similar to the price-to-sales but replaces the sales variable with earnings.

So many variables.