[Jefff]

pawn Code:

bool:IncorrectModel(modelid)
{

    for(new i=0; i != sizeof(RandomRegularVehicle); i++)
        if(RandomRegularVehicle[i][0] == modelid)
            return true;

    return false;
}

if(!IncorrectModel(CarInfo[idx][cModel])) return SendClientMessage(playerid, COLOR_RED, "You cannot sell this type of vehicle here");