If you paint over dirty, oily surfaces, the paint will easily chip or peel off. So before painting, clean grimy areas with a deglosser or heavy-duty cleaner intended for prepaint cleaning. They work well to clean painted, varnished or enameled surfaces to improve the adhesion of the new paint. They’re ideal for cleaning greasy or oily areas like kitchen and bathroom walls and removing hand marks around light switches and doorknobs.
When painting the trim, you don’t have to be neat. Just concentrate on getting a smooth finish on the wood. Don’t worry if the trim paint gets onto the walls. You’ll cover it later when painting the walls. Once the trim is completely painted and dry (at least 24 hours), tape it off (using an “easy release” painter’s tape), then paint the ceiling, then the walls.
If you decide to hire help, have several contractors inspect the job and provide proposals. You'll probably find huge price differences for the same job. A Checkbook undercover shopper got quotes from nine Washington-area contractors to repaint the walls, ceiling and trim for a living room, dining room, family room, bathroom and kitchen. Including paint and supplies, prices ranged from $2,650 or less to more than $6,500.
I am in northern Nevada and you have not yet gotten sufficient responses to provide a painting cost chart showing the averages. I do have a quote from an outside (Not Homeadvisor referral) painter who is local for $2,750 for soffits, patio cover and posts, Garage facia (redwood clapboard above (~300 ? Sq. Ft.) on a 2046 Sq. Ft. home where the walls are 9 ft tall and it is fully stuccoed with plastic stucco surfaces, so not being painted.