Why might a person agree to become an indentured servant and work for no pay? to help you answer here's a source;

Jamestown was settled in 1607. Over the years, it grew into a larger colony: the Virginia Colony. The Virginia colonists made their living by growing tobacco. It took a lot of workers to plant, take care of, and harvest this crop. Landowners forced enslaved Africans to do much of this work. The first Africans arrived in Virginia in 1619.
Not all workers were slaves. Many were indentured servants. These were people who agreed to work for a certain number of years for no pay. In exchange, their employers paid for their voyage to the colony.
In 1634, a new colony, called Maryland, began north of Virginia. Maryland was the dream of Sir George Calvert, Lord Baltimore. He wanted to found a colony where Catholics could practice their religion freely. At this time, Catholics in England were persecuted. Calvert’s son, Cecilius, worked to start the colony.
Cecilius offered free land to settlers who would come to Maryland. Upper class Englishmen were given large amounts of land. Average colonists were given less land. As in Virginia, wealthy landowners used enslaved Africans and indentured servants to do the work.
Before long, there were more Protestants than Catholics living in Maryland. To protect the Catholics’ religious freedom, the colony passed the Act of Toleration in 1649. However, the law did not end tension between the colony’s Protestants and Catholics. Eventually Maryland named one Protestant church as the official church of Maryland.
Other tensions arose over Maryland’s border with its northern neighbor, Pennsylvania. For many years, the two colonies argued over the exact location of the boundary between them. They finally agreed to settle the dispute once and for all. They hired Charles Mason and Jeremiah Dixon to map the border. This boundary became known as the Mason-Dixon line.
Virginia also experienced troubles during this time. James Berkeley, the governor of Virginia, promised Native Americans that settlers would not go farther west into their lands. Nathaniel Bacon was a farmer in western Virginia. He did not like the promise Governor Berkeley had made. In fact, many people in western Virginia did not like it.