[Y_Less]

OK, run these two modes together and look at the output:

pawn Code:

#include <a_samp>
new totalVeh  = 0;

#define GetTotalVehicles1() totalVeh

stock GetTotalVehicles2()
{   
    new vehc = 0;
    for(new x; x != MAX_VEHICLES; ++x) {
        if(GetVehicleModel(x)) vehc++;
    }
    return vehc;
}

forward InternalCVeh(modelid, Float:x, Float:y, Float:z, Float:angle, color1, color2, respawn_delay);
public InternalCVeh(modelid, Float:x, Float:y, Float:z, Float:angle, color1, color2, respawn_delay) {
    return CreateVehicle(modelid, x, y, z, angle, color1, color2, respawn_delay);
}

forward InternalDVeh(id);
public  InternalDVeh(id) {
    return DestroyVehicle(id);
}

#define CreateVehicle   totalVeh ++, InternalCVeh
#define DestroyVehicle(%0)  totalVeh  = GetVehicleModel(%0) ? totalVeh  - 1 :totalVeh ,  InternalDVeh(%0) 

main()
{
}

public OnGameModeInit()
{
    CreateVehicle(520, 2109.1763, 1503.0453, 32.2887, 82.2873, 0, 1, 60);
    printf("You have %d or %d vehicles on server", GetTotalVehicles1(), GetTotalVehicles2());
}

pawn Code:

#define FILTERSCRIPT

#include <a_samp>
new totalVeh  = 0;

#define GetTotalVehicles1() totalVeh

stock GetTotalVehicles2()
{   
    new vehc = 0;
    for(new x; x != MAX_VEHICLES; ++x) {
        if(GetVehicleModel(x)) vehc++;
    }
    return vehc;
}

forward InternalCVeh(modelid, Float:x, Float:y, Float:z, Float:angle, color1, color2, respawn_delay);
public InternalCVeh(modelid, Float:x, Float:y, Float:z, Float:angle, color1, color2, respawn_delay) {
    return CreateVehicle(modelid, x, y, z, angle, color1, color2, respawn_delay);
}

forward InternalDVeh(id);
public  InternalDVeh(id) {
    return DestroyVehicle(id);
}

#define CreateVehicle   totalVeh ++, InternalCVeh
#define DestroyVehicle(%0)  totalVeh  = GetVehicleModel(%0) ? totalVeh  - 1 :totalVeh ,  InternalDVeh(%0) 

public OnFilterScriptInit()
{
    CreateVehicle(520, 2109.1763, 1503.0453, 32.2887, 82.2873, 0, 1, 60);
    printf("You have %d or %d vehicles on server", GetTotalVehicles1(), GetTotalVehicles2());
}

I'm not even bothered about AddStaticVehicle/Ex at this point.