Frost??leak??? what's goign on??

I am planning on installing trim around some existing windows. This is in a new house and they trimmed the windows with drywall except a simple stool and apron. My plan was to remove the drywall to the studs and install wood jams and a header as well as a new stool, apron and of course casing. I just want to make sure this is the right way to go about this. I plan on using 3 1/2“ fluted casing with solid corner blocks (this matches my fireplace surround). In my living room I have 3 windows next to each other (about 11" between each) and was planning on making a continuous stool and apron but casing them separately. Do I sound like I am on the right path? Also when you use fluted casing what style trim would you use for the apron? Thanks in advance for the help. Steve

Our back door opens outward into our back patio. We would like to reverse it so it opens inward into the house. The reason being we'd like to install a glass storm door so we can keep an eye on the kids without letting in bugs. I'm sure it can be done since the frame around the door is wood, but how expensive would this be to do. I haven't called out for bids yet, but I'd like to know what my window of cost might be. I should add my patio is covered, but it wasn't when we had the house built, which is probably why the door was positioned on the outside of the door frame to prevent rainwater from getting inside.