Yes, a commoner can read Mūlācāra and Bhagavatī Ārādhanā, but they are deep and advanced texts of Jain Dharma.

• Mūlācāra mainly teaches the conduct and discipline of monks, especially in the Digambara tradition.
• Bhagavatī Ārādhanā is also a profound scripture focused on right spiritual conduct, fasting, endurance, and inner purity.

For a common person, reading them is not forbidden. However, it is best to read them with:

• humility
• proper understanding
• guidance from a ज्ञानी साधु / विद्वान
• and a sincere intention to learn Jain values

A commoner should especially be careful not to misunderstand the strict rules meant for ascetics as direct household duties.

So, yes, they may be read, but they should be studied respectfully and thoughtfully.