Best way to asses a buy and hold deal?

[Jason Woodrow]

Total newbie here. What are some effective ways to asses whether a buy and hold deal is a good investment? I'm interested in building single family portfolio (slowly) and would love to know formulas and tips on how to get good deals.

Any tools to help? Do these numbers change based on investment goals and if so, is there are there any standards I should be following or looking for? Thank you.