diff --git a/binance/symbol.go b/binance/symbol.go
index 0ca324d..24fadd2 100644
--- a/binance/symbol.go
+++ b/binance/symbol.go
@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"math"
 	"strconv"
+
+	"github.com/adshao/go-binance/v2"
 )
 
 // SymbolBalance get available amount in user wallet.
@@ -42,3 +44,13 @@ func (me *Binance) SymbolPrice(symbol, buyWith, interval string) (float64, error
 
 	return symbolPrice, nil
 }
+
+// SymbolExchangeInfo get the last symbol price.
+func (me *Binance) SymbolExchangeInfo(symbol string) (*binance.ExchangeInfo, error) {
+	res, err := me.Binance.NewExchangeInfoService().Symbol(symbol).Do(*me.Context)
+	if err != nil {
+		return nil, err
+	}
+
+	return res, nil
+}
diff --git a/bot/bot.go b/bot/bot.go
index 1b03745..9a49e44 100644
--- a/bot/bot.go
+++ b/bot/bot.go
@@ -168,6 +168,21 @@ func (me *Bot) sell(trade config.Trade, price float64) error {
 	return nil
 }
 
+// check rules before buy.
+func (me *Bot) rules(trade *config.Trade) error {
+	exchange, err := me.Binance.SymbolExchangeInfo(trade.Symbol)
+	if err != nil {
+		return err
+	}
+
+	minNotional := exchange.Symbols[0].MinNotionalFilter().MinNotional
+	minQuantity := exchange.Symbols[0].LotSizeFilter().MinQuantity
+	me.Log.Debug().Msgf("[%s] minNotional=%.2f minQuantity=%.2f",
+		trade.Symbol, minNotional, minQuantity)
+
+	return nil
+}
+
 // format welcome message notification.
 func (me *Bot) welcomeMessage(config config.Config) string {
 	msg := fmt.Sprintf("%s started! :money_mouth_face:\n\n", config.Name)