In PA you need to be careful, the state is pretty good about catching onto deals and consider places sold. not only would the owner have capitol gains but then he and you guys would have to pay transfer taxes as well, total of 2% ( 1% each usually). 

@Kevin Burton usually main other way is using a partner 

Usually Cap Rate gets me into the ball park and facilitates the decision to make an offer or not and at what price.

I have never had a mortgage take my first offer, but usually they countered. 

Credit Card  and HELOC loans are usually a last resort and require much discipline and responsibility when the bulling statements come and keeping their payment requirements done on time and paid off as soon as possible. 

(not so important but if they only require 15% down on a single family home that is usually a good sign that you are working with a flexible lender) Can I change title to my LLC?

What do you guys usually use as your assumptions for back of the envelope evaluations?

Garages are usually for storing vehicles and other stuff, not entertaining your boss.

When we do our taxes we break our the big table and categorize receipts (which usually have notes written on each one). 

I usually charge 20 - 25% more for a month-to-month extension to offset the potential vacancy during the slow season.This is your rental and your business.