What if my association has no location in its common area for posting board meeting notices/agendas? Is notice by mail to all members sufficient under Davis-Stirling requirements?

No. Posting is required on common area. If an association has common area that can accommodate a small sign it probably must install and maintain one. Also, an association could use a “sandwich board” on common area to announce the meetings. If no common area exists, mailing would probably be sufficient under Civil Code §1363.05(f).

What are the notice requirements for board meetings? Are members required to be notified as well?

Generally, unless the bylaws set the time and place or provide for longer notice, members must be given at least 4 days notice of the time and place of a board meeting. (Civil Code §§1363.05(f) and (i), Corporations Code § 7211(a)(2))