When to authorize after-hours calls to plumber or electrician?

[Aaron M.]

I live in California and have a "professional renter" (he is very knowledgeable about the lease and laws and acts strictly within those bounds - I perceive him to be a potential lawsuit threat) in my rental property.  Fortunately, I have a natural tendency to do the right thing and in a timely manner so his complaints to have "safety" issues addressed are not too much of an inconvenience for me (although the renter himself is an annoyance).  I am going to go on vacation for 10 days and I want to be clear on when I should authorize calling a plumber or electrician after business hours to address an issue.  Obviously, I am going to authorize an after-hours call to a plumber if there is a leak that results in water accumulating  under the bathroom sink (preventing property damage is a no-brainer); however, if a toilet is clogged, the water heater stopped working, electric power is no longer coming into a section of the house, then I dont want to pay the premium to have the tradesperson come after-hours (I dont feel like paying a premium for the convenience to my renter) when the call can be made the following day or on Monday if the issue occurs on Sunday morning.  

I know that by law (regardless of what a lease may say) landlords are supposed to provide basic amenities (hot water, electricity) to renters, but what are the timelines that such services need to be made available to the renter when there is a plumbing or electrical failure? 

I want and will be in compliance to the fullest extent of the law, but to be truthfully honest, I dont want to go any further for this particular renter than what I am legally supposed to do and I want to be ready if the late night plumbing call comes and I am on vacation.