House upgrades are not planned as far as i know, clothes you can buy from Ammelies go out after you talked a couple times to your Bot.
and correct me on that but i think you need all Limbs attached, i think
Viewing post in where can i buy clothes
Yes, once you visit Annalie's Shop and spend enough money on clothes she will ask you about bringing your "Girlfriend" to her shop.
To do so, Jun needs to have Both Arms and Legs and also needs to wear Clothes that can cover up her body parts such as a Bra, Underwear, Stirrups or Stockings, a Skirt or Baggy Pants, a T-Shirt, and a Hoodie.