Сделать ограничение на меню.

#include <amxmodx>
#include <aes_main>
#include <azp_weapons>

#define PLUGIN    "cso_weapons"
#define VERSION    "0"
#define AUTHOR    "kostya-lord"

new const STARTMENU 3 // 3 - раунд с которого открыт доступ к меню
new start_menu = 0

public plugin_init()
{
    register_plugin(PLUGIN, VERSION, AUTHOR)
    register_event("HLTV", "NewRound", "a", "1=0", "2=0")
    register_clcmd("cso", "server_menu")
    register_clcmd("/cso", "server_menu")
    register_clcmd("cso", "server_menu" )
    register_clcmd("cso_weapons", "server_menu" )
}

public NewRound()
{
    if(start_menu < STARTMENU)
            start_menu++
}

public server_menu(id)
{
    if(start_menu == STARTMENU)
    {
        client_print(id, print_chat, "Доступ к покупке открыт с %i раунда.", id, STARTMENU)
        return PLUGIN_HANDLED;
    }
    else cso_menu(iPlayer);
    
    return PLUGIN_HANDLED;
}

public cso_menu(id)
{
    new i_Menu = menu_create("[CSO] Покупка оружия за кредиты", "MMENU" )

    menu_additem(i_Menu, "\r[CSO] \wГитара\ - [10]" , "1", 0)
    menu_additem(i_Menu, "\r[CSO] \wУничтожитель\ - [11]", "2", 0)
    menu_additem(i_Menu, "\r[CSO] \wМега Фамас\ - [9]", "3", 0)
    menu_additem(i_Menu, "\r[CSO] \wМега Береты\ - [7]", "4", 0)
    menu_additem(i_Menu, "Thompson\r[CSO]\ - [11]", "5", 0)
    menu_additem(i_Menu, "K1ASE\r[CSO]\ - [9]", "6", 0)
    menu_additem(i_Menu, "VSK-94\r[CSO]\ - [10]", "7", 0)
    menu_additem(i_Menu, "Winchester M1887\r[CSO]\ - [6]", "8", 0)
    menu_additem(i_Menu, "SPAS-12\r[CSO]\ - [13]", "9", 0)
    menu_additem(i_Menu, "M95\r[CSO]\ - [14]", "10", 0)

    menu_setprop(i_Menu, MPROP_NEXTNAME, "Вперед")
    menu_setprop(i_Menu, MPROP_BACKNAME, "Назад")
    menu_setprop(i_Menu, MPROP_EXITNAME, "Выход")

    menu_display(id, i_Menu, 0)

    return PLUGIN_HANDLED
}

public MMENU(id, menu, item)
{
    if (item == MENU_EXIT)
    {
        menu_destroy(menu)

        return PLUGIN_HANDLED
    }

    new s_Data[6], s_Name[64], i_Access, i_Callback

    menu_item_getinfo(menu, item, i_Access, s_Data, charsmax(s_Data), s_Name, charsmax(s_Name), i_Callback)

    new i_Key = str_to_num(s_Data)

    new rt[4]
    new bool:status = aes_get_player_stats(id,rt) != 0 ? true : false

    if(status)
    {
        if(rt[AES_ST_BONUSES] <= 0){
            client_print(id,print_chat,"Недостаточно бонусов!")
            return PLUGIN_CONTINUE
        } else if(rt[AES_ST_BONUSES] <= 10) {
            aes_add_player_bonus(id,-10)

        }
    }

    switch(i_Key)
    {
    case 1:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 10){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 10) {
                    aes_add_player_bonus(id,-10)
                    give_weapon_guitar(id)
                }
            }
        }
    case 2:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 11){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 11) {
                    aes_add_player_bonus(id,-11)
                    give_weapon_pkm(id)
                }
            }
        }
    case 3:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 9){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 9) {
                    aes_add_player_bonus(id,-9)
                    give_weapon_qbb95ex(id)
                }
            }
        }
    case 4:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 7){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 7) {
                    aes_add_player_bonus(id,-7)
                    give_weapon_infi(id)
                }
            }
        }
    case 5:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 11){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 11) {
                    aes_add_player_bonus(id,-11)
                    give_weapon_thompson(id)
                }
            }
        }
    case 6:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 9){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 9) {
                    aes_add_player_bonus(id,-9)
                    give_weapon_k1ase(id)
                }
            }
        }
    case 7:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 10){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 10) {
                    aes_add_player_bonus(id,-10)
                    give_weapon_vsk94(id)
                }
            }
        }
    case 8:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 6){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 6) {
                    aes_add_player_bonus(id,-6)
                    give_weapon_m1887(id)
                }
            }
        }
    case 9:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 11){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 11) {
                    aes_add_player_bonus(id,-11)
                    give_weapon_spas12(id)
                }
            }
        }
    case 10:
        {
            if(status)
            {
                if(rt[AES_ST_BONUSES] < 14){
                    client_print(id,print_chat,"Недостаточно бонусов!")
                    return PLUGIN_CONTINUE
                } else if(rt[AES_ST_BONUSES] >= 14) {
                    aes_add_player_bonus(id,-14)
                    give_weapon_m95(id)
                }
            }
        }    
    }

    menu_destroy(menu)
    return PLUGIN_HANDLED
}