After playing the demo I feel the same sensations as with Moonligther, a game that makes you addicted to the continuous feeling of buying and selling and it's great.
Problems I see:

-The demo has the mistake of not making it clear that you can travel to the world of storage rooms and that is a huge mistake because it suggests that the game ends in the store.

-The feedback of all your actions is terrible, and the sound is not very good, I'm surprised that with such a nice art style and quality gamefeel does not feel that tasteful, I would like to feel that entering the computer does not feel orthopedic, also do not notice that you do not walk on the air and your actions have weight and importance, also the sound as such of the effects is not noticeable only you stay with the music that stands out too much.

For the rest I think you can make a viral and successful game, but above all you have to give value to a possible space exploration and make all interactions have a more pleasant and physical feeling.
Good luck with the development! You have a diamond to polish.