How to add value to residential property?

[Jesse Torres]

If the After Repair Value of a Single Family house is $120,000 and I want to add value to it, how do I determine how much value is added to it if lets just say I add a 3rd bedroom to a 2 bedroom house. If I spend an extra $4000 to make the house stand out so that it will sell quickly, how much value am I adding to the house. Is there a chart or a formula to figuring this out?