Missed service because the unit was behind a fence: who's responsible?

In most cases the missed trip is on you, because the contract made access your job and the gate was locked when the driver showed up.

A service visit runs on a fixed route, so the driver usually has a short window at each stop and no time to wait around or track down a homeowner. Most rental agreements say the customer keeps the unit reachable on service day, and a locked gate counts as blocked access. Whether they were supposed to call first comes down to your paperwork. Read the service section of the contract. If it promises a call or text before a skipped stop, you have a real argument. If it says nothing, the charge is usually fair.

What I'd do, having been through this on my own remodel:

• Call the office, explain it was a one time mixup, and ask if they'll waive it as a courtesy. A lot of them will the first time.
• Ask them to come back out early so the unit doesn't go two weeks without a pump.
• Leave the gate unlocked on service day, or give them a lockbox code or a padlock combo they keep on file.
• Put a note on the gate with your cell number so the next driver can call instead of leaving.

We ended up moving ours just outside the gate for the rest of the job and never had the problem again.