1) Come to the Headquarters!
2) Find the watermelon somewhere...
3) Buy it and find the landmark to #002 inside your new folder.
Teleport to the 2nd store location.
4) Find and buy the watermelon hidden inside the 2nd store.
You will find the landmark for #003 inside another new folder.
You may use the hints to help you through.
If that does not help, you may join the group to ask for help: