Please disregard my first post. The County site shows the following useful Q&A:
How do I obtain a Rental License to rent my single-family house?A rental license is required to rent a single-family dwelling with the following exceptions: the tenant is the landlord's parent, son, daughter, sibling, grandchild, grandparent or in-law; the landlord is an active member of any branch of the United States Armed Forces, Diplomatic Corps, or Foreign Service who maintains the subject property as her or his domicile and permanent residence; or the landlord has been relocated for employment or education, maintains the subject property as her or his domicile and permanent residence. A rental license application can be obtained from Housing Enforcement at (301) 883-6100.
Ariana provided you fantastic information. But please be sure to hire a reputable management company. I don't represent any but there are some great ones listed right on the web. I have heard so many nightmares from past clients and family members who DID NOT take this advice. It all seems so simple but it can be much more difficult that it appears especially once the problems begin.
All the best!