Thank you all so, so much. This is very helpful.
I went to the craft store "garage sale" and got a textured scrapbook paper that looks like a tin ceiling. Nine year old Buglette painted it and is ready to put it in. Once people found out what she was doing, they gave us many other pieces of scrapbook paper for wallpaper, so when she's ready we have some fantastic possibilities there. We also found paint on Lowe's 'oops' rack, which I think she will use on the outside eventually. She egg-carton flagstoned the foundation and it looks great!
Emily, we've been following your walkthrough on the Fairfield for the last week, and it's been very helpful. I'm learning to let her do it instead of thinking it needs to be just-so.
I love all of the suggestions for lights. I'm not sure which direction she's going to head -- on our very toe-dip into lights, she was certain she wanted round wiring, but I'm looking at tape and it makes so much more sense for her skill level. The LEDs from Amazon might also be the direction we head since it is her first dollhouse; but I think she has her heart set on a chandelier. Maybe a combination of the two : battery operated options give us that choice, don't they?
Again, thank you all so very much. This is seeming much less daunting.