I have only one comment about adding 1000 square footage to your existing home, be sure it's not an over improvement for your neighborhood. Being the Biggest home on the street may be that you will not get back what you paid in for that improvement, or such a small amount, it will not the best thing to do. Just check to see what is going on around you. Too many folks improve their homes, to a level that is so much more than what's around them, they can't sell their homes. Or not anywhere near what they feel they put in. It's always the next owner you need to think about, unless you plan on being there for such a long time that the neighbors improve to your level, that does not happen that often. Just be careful.
Best to you!