MLOS: You can walk into a home and it has a set up interior with furniture, if it says "unlock" on the door it has been purchased and these are only purchasable with Half Life Coins
SHELLS: Homes you can not walk into and a shell (interior) will be added where you can put in your own furniture bought in city , if it says "knock" on the door when you press tab then it has been purchased.
Prices may fluctuate based on features location and size. Realtors set pricing is final.
