A recent post in a different game reminded me of something. Unless we're in combat, or unless you state otherwise, I am assuming that you are "taking 20" on the following skill checks: Search and Open Locks. Both of these skills are full-round actions, which means that "taking 20" takes about 2 minutes to complete, which is not an unreasonable amount of time. Also, both of these skills don't have immediate negative consequences, so you can just keep on trying. There will be exceptions to this rule, given the circumstances, but unless anyone has a problem with this or states otherwise, I'll assume you're "taking 20".