[ReVo_]

#define MAX_BUY_PLACES 2
new Float:buyPlaces[MAX_BUY_PLACES][3] =
{
{x, y, z},
{x, y, z}// etc
};

In the command:

for (new i = 0; i < MAX_BUY_PLACES; i++)
{
if (IsPlayerInRangeOfPoint(playerid, 5.0, buyPlaces[i][0], buyPlaces[i][1], buyPlaces[i][2]))
{
// is near the point
break;
}
}