[efeX]

Look, it takes a couple simple variables and a command. Here..

Код:

new gPlayerLevel[MAX_PLAYERS]; // above main()
new gPlayerMoney[MAX_PLAYERS];

public OnPlayerCommandText(playerid, cmdtext[])
{
  if (strcmp(cmd, "/buylevel", true) == 0)
  {
    gPlayerMoney[playerid] = GetPlayerMoney(playerid);
    if (GetPlayerMoney(playerid) >= 250000)
    {
      gPlayerLevel[playerid] += 1;
      SetPlayerMoney(playerid, gPlayerMoney[playerid] - 250000);
    }
    return 1;
  }
  if (strcmp(cmd, "/flip", true) == 0)
  {
    if (gPlayerLevel[playerid] > 1)
    {
      SendClientMessage(playerid, 0xFFFFFFFF, "I just... flipped?");
      return 1;
    }
    else
      return SendClientMessage(playerid, 0xFFFFFFFF, "You are not high enough level to use this!");
  }
}

Not tested, but should work.