Slavery in the Roman Empire is perfectly legal, and although slaves are a small percentage of the population it is very rare to find an adult who has not met at least one.
The largest slave owner is the state, which uses them primarily for the maintenance of public facilities, both as workers and as cleaning personnel, technicians, etc.
The second largest owner is the large corporations, who use slaves fundamentally as the state: as cheap laborers of low ability.
Finally, there are private slave owners, who tend to be very wealthy people, since not only the purchase of a slave is expensive, but also its maintenance.
Thanks to various laws passed over the centuries, slaves have a series of rights, although perhaps it would be better to say that the owners have a series of duties: in fact, a slave can neither be killed nor tortured both physically and mentally; they must be given decent living conditions (sufficient food, shelter from atmospheric elements, etc.) and can contact specialized lawyers in case of ill-treatment; sexual violence is part of the condemned torture, but often it is not reported and the owners have an easy time claiming that the relationship has been paid with gifts to the slave involved, such as better meals; this does not apply if the slave is a minor (16 years), in this case it is always considered torture.
A master can free a slave at any time, as well as resell it if he wishes, but if he is released he must pay a 2-month salary for the slave's profession, and if he sells it he must make sure that the buyer has not pending charges that prohibit the possession of a slave.
The children of a slave are always considered slaves in their turn, unless a master decides to recognize them as their children, in which case they are considered free citizens (in case the owner is an abstract entity, like the state , a parent is established among the free personnel).
Slave children can not be separated from parents till they are 6 years old, after which they can be sold freely.
Often slaves that are to be sold to individuals are raised in so-called "slave mills", where specialized specimens are mated together to obtain better slaves, which are then educated in specific schools for their field.
Each slave is equipped with a chip that monitors both the condition and the position, making it easy to capture the fugitives, and is programmed to give the alarm in case it is removed.
Most of the slaves currently existing are children of slaves, even if there is a percentage of people who have been enslaved for debt, since it is possible to enslave their debtors if their debt reaches the amount that could be obtained by selling them to the market.
Another minimal but existing part of the enslaved population is composed of voluntary slaves, often people without property or family who decide to sell themselves as an alternative to living on the streets. In these cases slavery has a set time limit during the sale, and the purchase amount is paid at the end of the slavery period to the slave.
There is only one option for a slave to be free: exceptional skill not only in their own profession but also to convince their owners or controllers to let them be free.
Payment & Reimbursement
Obviously there is non payment for slaves, since they cannot own anything.
The purpose is to have people who work but don't need payment.
Lowest of the low. While technically considered people slaves don't have rights.
The total percentage of slaves is 2% of the overall population.
While slavery existed from the foundation of Rome they gained rights during the millenia, but are still considered more tools than people.
The tools vary, based on the specific occupation of the slave. While not a tool all slave have a chip implanted under their skin that controls them.
Varied. But mostly heavy and unskilled labor.
Dangers & Hazards
While killing slaves is illegal there have been many "casual" deaths among them.