@iJustDrevay - the mortgage have nothing to do with determining whether there is a capital gain.
Capital gain is simply Selling Price Less Selling costs Less original Purchase Price less improvements.
If you "walked away with $499k" but that statement includes paying off the mortgage, then you walked away with a lot more than $499k in terms of capital gains.
If you are selling this 2nd home for convenience, you must have lived and owned the home for the past two years to be eligible for the exclusion. Further, the sale date of this home must be at least two years from the sale date of the first home, as you are only eligible for ONE exclusion every two years. So if you have lived in this home for 14 months, but just sold the first home two months ago and took the exclusion on that home, you have only satified two months of the 24 month requirement so far on this second home..
