Need info about maintenance painting

[Guest guest]

Does anyone know anything about stucco and how often building exteriors need to

be painted to keep water out?

This is a building that's nearly 100 years old and the exterior hasn't been

painted in at least 17 years (that's how long tenant memory goes back). In the

rainy season, the inside walls would get soft in patches, seemingly from water

coming in through cracks in the exterior. The cracks have been patched, but I'm

still thinking it needs a coat or two of paint to seal it better. Anybody

experienced in this?

Thank you,

~Haley