[miokie]

Just make a check for each player with a simple array, when the player has typed the command in Check if the array = 1, if it dosen't Set it to 1 and spawn the vehicle.

Example:
At the top of yoru script:

pawn Код:

new HasSpawnedCar[MAX_PLAYERS];

In yoru command:

pawn Код:

if(HasSpawnedCar[playerid] == 0)
{
HasSpawnedCar[playerid] = 1;
//Spawn the vehicle here..
}
else
{
SendClientMessage(playerid,COLOR," You have already spawned a vehicle!");
}

I hope you understand what I mean.