Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
Marmac you are right. It is all theoretical but I think as a potential home seller or buyer you should know all the tax implications involved. Most likely they will not have to pay capital gains tax but you have to declare the sale of your houses on your return.
Also I am of the opinion the OP should not pay extra on the mortgage but rather save that amount for the next down payment or other expenses.