Listening to the podcasts and reading various books/blogs/articles, I've noticed the phrase "meets our criteria" or some variation thereof used often. I'm wondering how you go about deciding what your criteria are? So far I've gathered that you need to know what you want to use the property for, but beyond that it seems like guesswork. Does anyone have a list they use, or some kind of boilerplate method for writing down your criteria? Can anyone recommend any good resources for determining what a realistic ROI would be in your market? I'm not even sure if I'm asking the right questions with this, but I've looked at a lot of different types of properties, and I'd like to form a better method of narrowing down the selection process. Any thoughts or suggestions are much appreciated.

I do buy and hold rentals. In my market I aim for a 1% monthly return on total outlay after expenses. That means if I buy a house for $50k I look for at least $500 clear per month. Not an easy thing to do where I am because there is a lot of demand for low-end houses and a cap of about $2k/monthly for market rent, but I have two right now that clear 12% & 14% annually, which is 1% & 1.2% respectively. If property taxes were higher here it would be very difficult to clear 1% monthly IMO. 

As far as the houses I have certain construction & location criteria that I use that I won't divulge on here ;) .