Wallpaper is a huge turn off for me. It's too much work to remove it and you never know what what condition the walls are going to be in once it's removed. Other turn offs for me: musty or mildew smells, houses that have been smoked in, dirtiness, dark rooms, water stains on ceilings, low quality windows, and bathrooms and kitchens that haven't been updated (we are not do it yourselfers and we wouldn't buy a house with outdated bathrooms or kitchen because it would be too expensive and frustrating for us to re-do those areas ourselves).
OP, here are a few observations and suggestions that may make your house show better and sell faster:
The dark brown wall color in the living areas is too dark. Repaint with a nice neutral color. You can google popular paint colors that are often used for staging homes for sale. These tend to be nice, neutral colors that appeal to a lot of people. Pick one of those and re-paint. Pull up the carpet squares and refinish and restain the hardwoods if possible. Declutter everything. For resale purposes, you have too many pictures on the walls and they are hung way too high. I would also suggest removing the window treatments in the brown room. The single curtain panel looks odd in the pictures. Simple wood blinds would be much better (not vinyl or aluminum). The open bedroom closet is much too full and the stuff in it needs to be reduced by at least three quarters. All of the stuff in the nightstand needs to be removed as do the stickers on the closet door. Regarding the exterior, I would get rid of the metal swing set in the back yard. As you already know, the outside of the house needs to be repainted. The garage door in particular needs some attention as does the front porch. I haven't seen any pictures of the kitchen or bathrooms but those need to be spotlessly clean and decluttered for showings. If you do not have an updated kitchen and bathrooms, clean and decluttered is even more important. I am not sure what the problem is with the ceiling in the brown room. It looks like it has a buckle in it. That would concern me. Can it be fixed?
Good luck, OP. It's hard work selling houses in this market.