ooh, so thats what you meant by the market! ^^;
to clarify, the market on the home deka is pretty much just a shop where items rotate in and out in a certain cycle. on the store deka however, that's the entire purpose of it, so that you can buy items to send to your tamagotchi. it should definitely have more items on the store deka as that's the entire point of it.
and as for the locations, those are the house expansions for the blue home deka. the purpose of the home deka is to upgrade your house, as i said in my first post. the 9999 GP thing you're talking about are house expansions; the 9999 GP one being the final one. inside the wikia page I linked you it says:
"one can upgrade their house several times, the end result being a large Japanese-style palace."
those 2 items are from my understanding the last 2 expansions you're able to get.