Dua when entering a marketplace (or shop etc.)”,لَا إِلَهَ إِلَّا اللهُ وَحْدَهُ لَا شَرِيكَ لَهُ ، لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ ، يُحْيِي وَيُمِيتُ وَهُوَ حَيٌّ لَا يَمُوتُ ، بِيَدِهِ الْخَيْرُ وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ
The messenger of Allah (may the peace and blessings of Allah be upon him) said: Whoever enters the market and says:
“None has the right to be worshipped except Allah, alone, without partner, to Him belongs all sovereignty and praise. He gives life and causes death, and He is living and does not die. In His hand is all good and He Omnipotent over all things.”
..Allah will wipe a million bad deeds from his record and grant him a million good deeds, and will elevate him a million degree (of virtue)- ([and will build him a house in paradise] in another narration).
laa ilaaha ill-allaahu waḥdahu laa shareeka lah, lah-ul-mulku wa lahul-ḥamdu, yuḥyee wa yumeetu wa huwa ḥayun laa yamootu, bi yadi-hil-khayru, wa huwa ‛alaa kulli shay’in qadeer
Sources: At-Tirmidhi No# 3428 and 3429; Ibn Majah No# 2235 and others. See also Sahih Al-Kalim Al-Tayeb No# 230