Salt leaves a thin film
You may not see it, but salt can sit on the wall. Paint should not be placed over that film.
Metal can rust faster
Fasteners, railings, doors, and small metal parts can show rust near the coast. Rust needs its own prep.
Wind can carry spray mist
Beach wind can change a spray day. A safe job may need brush and roll work or a better weather window.
Sun and salt work together
Strong sun dries and fades the coating. Salt and damp air add more stress.
Rinse, dry, and coat with care
A clean fresh-water rinse, full dry time, correct primer, and suitable finish give the wall a better start.
What to do next
Look for salt film and rust near doors, rails, and fasteners. Rinse before you judge the paint.