In looking through my taxes for 2012 I realized I have made a few errors for 2011.

For 2011 taxes:
- I did not include the mortgage interest I paid on a HELOC
- I did not list the tuition I paid for my masters degree classes
- I did not include car registration fees or excise tax

Based on amending those items in Turbo Tax for 2011 it looks like I may be due a refund of an additional $500 or so.

I'm also questioning the interest on my first mortgage--for 2011 I put down that I paid $10,077. But for 2012 my bank's statement says that I paid $10,700. The principal on the mortgage is decreasing, and the rate is fixed... so I don't understand how I could have paid less interest in 2011 vs. 2012? I'm starting to wonder if I accidentally entered $10,077 when it fact it may have been $11,077? (it was a manual process from a 1099-INT, was not imported). If I did make an error here it would be another $300 or so back to me.

My question is... how difficult is it to file an amended return? I filed electronically last year, so I provided no paperwork or receipts. Assuming that I can find all the required receipts/paperwork they need with the amended return, does this typically "wake the sleeping giant", or is it a fairly common thing?

I don't need the $500-800, but if doing 2-3 hours worth of paper work can get it, I certainly will do it as long as it doesn't open a can of worms.