A blessing in disguise?

Back in January, when the garage project was just beginning, we refinanced our second mortgage to Penfed's 5.99% fixed, 20-year, HEL in order to get more cash out and take advantage of their lower rate. Without the new garage and man room built (at that point we had no garage, and only a portion of our driveway left, the front of the house was a disaster), our house appraised at $230,000, $5,000 more than it had been appraised for by a different appraiser just seven months prior. Since our old garage was unusable and an eyesore, we weren't shocked that the appraised value went up slightly after it was torn down. Our intention was to refinance AGAIN once the new garage was built, and move what was left of the garage debt from our 0% credit cards onto the fixed HEL. Little did we know that we would get an absolutely incompetent appraiser, who, in his defense, is not from this area, who would appraise our house, with the $50,000 new garage, man room, and driveway, for $200,000. That's a $30,000 price DECREASE in just four months, plus we have added a lot of value to the house in that amount of time. We expected an appraisal, and my own research supports this, in the $250,000-$260,000 range. The housing market in this area is still fairly strong. So, in summary, we spent $50,000, expected a $20-30,000 increase and instead got a $30,000 decrease. We are contesting the appraisal, but so far it looks like none of our credit card debt will be moving to the HEL. I thought I would be more upset about this than I am. We have $33,000 left in garage expenses on the credit cards, all at 0% until early next year. We have a $23,000 HELOC that we can use if necessary, which leaves $10,000 in debt that we need to be prepared to pay off at a moment's notice. Instead of wallowing in self-pity, I'm seeing this more of an opportunity to wipe this debt out quickly and get it over with. I think Mr. Savvy and I can spare about $1,600 from our monthly budget to throw at paying down the cards. In addition, we will be earning another $200 in interest on the remaining 0% money. This works out to us paying all of our credit card mins out of our monthly income, and not touching any of the existing credit card money that is currently in savings. If we can maintain this pace, we can pay this debt off in 18 months. I know we have a baby on the way, and some months will have unexpected expenses, so I think I two years is a reasonable amount of time when you throw in anticipated and unanticipated expenses. Maybe contesting the appraisal will work out, maybe it won't, but I think I'm more excited about the challenge of paying it off ourselves and getting it over with. I was shocked when I put the budget together and saw that our discretionary spending was in the thousands every month (we could probably throw $2,000+ a month at the debt if we really wanted to... and maybe we will get there, but that's a big step to take all at once).