Emily, I have living space in the basement of my new downsize which does not have windows. Everything has been redone, right down to the studs, so no issues with anything but the lack of natural light.I emailed a designer who frequently has stories on houzz for whom I have great respect and she has been very generous with her suggestions on what I should do. I also contacted a couple of houzzers who always seem to give great advice and were most generous with their ideas It is a design dilemma, that's for sure! Bottom line..for the rooms with no windows, I decided on a dark, saturated color which I chose from the BM CSP line. I used this line because there is no black or gray in the formula and colors are super rich. I did walls and ceiling in the same color, trim, super white in semi-gloss.When you enter a windowless room you always have to turn on lights anyway, so why not choose a color which will glow in the artificial light. Then use fabrics which contrast with the darker walls. I chose silk.Another tip, use up lights and buy the bulbs which mimic daylght.For one no-window room, I had my builder make a frame of an interior window, just as if it were 4 x 6 construction. My electrician used rope lighting around the inside edges, The fellows who installed the shower doors, put muntins over a piece frosted glass then installed the glass in side the window frame. Regular window treatments and it looks pretty darn good.My daughter has a fabulous huge basement room with no window. She hung drapes to the ceiling across a long wall, then in the middle she put one of the large canvas wrapped pictures of a river scene. Mimics a view out a window. Hope this helps.Wow! your uncle is one great guy!