You don't have to withdraw ammount of money every time.
Store users money in global var and set it everytime the money is changed. This will never give the user more money than 800 untill you give them some money. You'll have to use cshack if you wanna go lower than 800.
Code:
#include <amxmodx>
#include <cstrike>
new g_money[33]
public plugin_init() {
register_plugin("", "", "")
register_event("Money","msg_Money","b")
}
public msg_Money(id)
cs_set_user_money(id, g_money[id])