1031 Exchange for value of property less purchase price?

[Tambi Harwood]

I have a property that is worth about $465,000. I bought it in 2003 for $250,00 with the proceeds of my deceased mother's property that I sold. I thought I could 1031 it for the current value minus the amount I bought it for, or that that would be the only amount that I would need to have sheltered from capital gains. Am I thinking incorrectly about this? Probably, because that's what my CPA said. I'm thinking about buying a property for only $215,000. Would I be able to protect that amount using the 1031 Exchange and not worry about the other amount since it's not affected by capital gains?