What if the service truck can't get to my unit on a rainy day?

Brad is right that you will likely be billed for the attempted service, but the driver's call is a courtesy many operators extend. The standard rental agreement includes a clause about truck access. The operator cannot risk getting a vacuum truck stuck on private property. The solution is to move the unit closer to the street, within the 25-foot hose reach most trucks carry, or to lay down a temporary road of crushed stone or gravel over the mud. For a long-term rental, that stable access is your responsibility. You can ask the company for a one-time relocation to a serviceable spot, which may have a small fee.

Access problems that keep the vacuum truck off your driveway usually fall on the renter, not the rental company. Most contracts treat a weather no-go as a dispatched service visit they already spent fuel and driver time on, so the invoice keeps the charge even when the tank never got pumped.

I have had the same gravel drive turn into soup after two days of rain. Drivers will stop at the hard edge rather than risk burying a loaded vacuum truck. Fair or not, that is the norm. What you want in writing is whether they will come back for a make-up visit at no extra trip fee once the drive firms up.

Practical fix is placement. Keep the unit near pavement or lay temporary mats so hose reach works from the street. A unit sitting 150 feet down soft gravel is asking for a missed service. Also call ahead on wet weeks so they can slot a make-up before the tank gets ugly for the crew.