Check on an appraisers forum to see if there would be any difference in value. Unless you are getting cash for the sale or a large down payment from the buyer the appraisal will be the determining factor if you actually get more at the sale. If you do this change, do it for yourself and not for resale. If you do this change, make sure you don't make the current floorplan dysfunctional as that will take value away. If you are using the exact same square footage and not adding any, then it is doubtful that your home would add value but you would need to get twin sales in the area to see how much, if anything, is added to the value. It may open up the buyer pool and sell more quickly though. As the others mentioned consulting with a couple of Realtors in your area would help you get a handle on the current market.

What a beautiful room! Do you want to go cooler or warmer, with the rug/wall? Traditional or abstract/contemporary? From the bed I'd guess you want something more modern but trad would look good, too, and the light fixture, to me, is almost like a mix of industrial and Victorian. Gray is my favorite color; I've used it as my base throughout my house, and I've paired it with oranges, yellows, and blues in various rooms. (I love orange, too, so were it my room that's what I would do--a rug with a nice mix of shades and colors, and you can then pick out your favorites and use them on the wall and other decor.) But there are plenty of colors that would look lovely with what you have--maybe a deep subdued red or brick red for a dramatic look, or a seafoam or pale olive green if you want something more airy. And IMO you can never go wrong with navy or midnight blue and white/ivory--it goes with everything and suits every style and look--so if you want to keep it cool, that's where I personally would go. The lovely warm floor would keep white walls from being too sterile, I think, as would the pattern on the wall. Is that a fireplace across from the bed (far left corner of the second picture)? If so, a picture of that might help--what kind of surround does it have? Tile or brick or...? What color? Mantel? Again, it's a gorgeous room. I love the bed and fixtures and flooring, and all those windows! I hope I've been some help! Good luck! Whatever you decide, I'd love to see some photos, once you've decided/finished.

Requirements for egress differ from place to place. Where I live (Ontario Canada) it's enough to have an egress window somewhere in the basement, in addition to the main staircase exit. The window doesn't need to be in the bedroom. It may be different where you live, or you may want to put in a bedroom egress window even if your code doesn't require it. So be sure you budget for that expense if you don't already have what is required. The requirements for a legal bedroom, size-wise, also differ from place to place. If you want to list it as a bedroom when you sell, be sure you build it to the adequate size for your location.

I think from your yellow post-it you want a separate "apartment?" Besides the tying in to plumbing, the big design points with carport/patio captures are: - water: the slabs are at grade level, not above, so rotting of sill plates/bottom of siding. - footings: typically none on the perimeter of open slabs (e.g. thickened edge). All can be tackled with design, diligence, and a checkbook.