From what you say it sounds like the wood is dry, like a sponge. You
could go out there and put 500$ worth of primer on or get someone who
knows and Seal it 1st coat for 100 in primer. You have a house that
could suck you and paint dry unless you use a guy that knows old
Cypress.

Are interior studs 16" or 24" on center 24 and you need 5/8 minimum
Money pit.