Define Your Area And NeighborhoodResearch what kind of neighborhood you want to target. This will determine your price range, potential target buyers and also the level of rehab which would be needed.
Rehab costs: This is the cost to actually fix up the property. J Scott in his book on Estimating Rehab Costs provides a great template to capture all details.
Determine The Buy Price
To flip a house profitably; you need to run the numbers accurately. Do not fall in love with a property and then adjust your assumptions to make it look profitable on paper.