Rental comps, also called rental comparables, is a set of similar rental properties that have been rented recently and help the landlord set an appropriate market rent price.
Though landlords often want to maximize the amount of rental income they receive, they have to still be reasonable since tenants will not want to pay for a severely overpriced rental.
When establishing rental comps, it's important to select the right properties. For example, if the property investor owns a 1 bedroom apartment, it won't make sense to compare the rent prices to other 3-bedroom apartments.
Oftentimes, a property manager, an agent, or a broker may be able to point you in the right direction.