Since I don't know your Japanese level, I wrote the translations in 3 different levels: Kanji and hiragana combination, Roman-ji, and closest pronunciation I could imagine in aplphabet combinations.
1. 液体、化粧品、薬品は ありますか?Ekitai, keshouhin, yakuhin-wa arimasuka? (eh-key-tie, keh-show-hin, yak-hin wah ali-mas-kah?)
2. これは 大きすぎます。没収させていただきます。Kore-wa oukisugimasu. Bosshuu sasete itadakimasu.(koh-leh-wa oki-su-ghee-mas. bo-shoe-sas-seteh-ee-tah-dah-key-mas.)
3. OK!お気をつけて いってらっしゃい。OK! O-ki-wo tsukete itte rasshai. (OK! O-key-wo tsu-keh-teh it-teh-la-shy.)
4. こちらへどうぞ!Kochira-e douzo! (koh-chi-la-eh doe-zoh!)