After creating the room for the interior of the antiques store, I sat back and looked at it from a little further distance. It is still not fully done and already has a lot of details. There are more vases, chandeliers and old gadgets to be added. So the room will be packed with tons of trivial details.
I remembered a technique used in King's Quest V when King Graham enters some stores and houses. Out of the massive amounts of respect I have towards King's Quest V, instead of checking videos or screenshots online, I ran the game. And when I run King's Quest V, I must play it to the end :)
The idea I adapted is to use the exterior of the store as a background, while the interior is framed as a GUI with whatever desired bordering. As a cameo I used the frame used by King's Quest V with little alterations. I also desaturated the exterior background since the interior is very colorful.