Finally I have the confidence that I can replace the windows. the existing windows are vinyl double hung. I think it will not be too complicated-- take out the trim, remove interior stops, remove the screws , get the window out. However I have two questions-- 1) can I take the window out and measure the current window for most accurate measure? I can also take it to a mom and pop Home Improvement store and let them measure ( those mom and pop stores have more knowledgeable staff) 2) the online instruction says something like parting stop and sash liner. I don't think I see something like this . Removed the trims and looks like I can pull out the whole window , fill some more insulation in the hole in frame and just push another back. Am I missing something?

We replaced an original handle set in our front door to out in an electronic set. The old sets required large cutout of the door. So how we’ve got a big old hole on the inside of the door below the handle. I’ve thought about either filling or doing a brass plate but I’m not sure the best way to do either. I'm wondering if other have run into this before and what did you do. Thanks for your help!