It sounds like you are actually selling it to him for $155,000. That means you have a capital gain of $35,000 (minus the cost of any improvements that you have made).
If you owed the property for one year or less, your gain is taxed at your regular tax rate.
If you owned the property for more than one year, it is taxed at a lower rate. For most people, it is 15%.
However, that 'extra' income could affect other things on your tax return. So the only way to know is to enter all of your information into the tax program.
