[Jonny5]

im not giving you code here as you should by now be capable of searching and using the wiki for these answers

but heres the hint

pawn Код:

HouseEnter[id] = AddStaticPickup(1273, -1, x, y, z, 0);//Creating the checkpoint and storing it in the HouseEnter value.

you need to destroy this pickup when someone buys and then create a new one with the blue house icon!
1273 is the id of your current house icon,
that will need changed.

regards,

also you should not use AddStaticPickup
heres the links youll need.
https://sampwiki.blast.hk/wiki/CreatePickup
https://sampwiki.blast.hk/wiki/DestroyPickup