I restored a basket case Haunted House like this last year. You are in for a lot of work my friend.

My lower playfield looked just like that with the giant holes painted green. I was able to repaint it. The hardest part was painting those little blue "pebbles" back. Took hours! If you replace the playfields don't throw the old ones out, they are fixable.

I also had a lot of rust like you - I ended up sanding it all down, then primed with rustoleum, painted with a metallic paint and then a light clear coat.

Good luck. It's a great machine and well worth whatever effort it requires. I also took tons of pictures, so if you need anything let me know.

I looked at the multiball mod. It was pretty involved, figured I had enough on my plate.

Adding speech to this one just seems weird to me some how. The speech system sounds very robotic.