1. Propane seems to be able to reproduce itself. This makes it impossible to empty the LPG tank, even if you run the furnace nearly full time for days on end while traveling to the port on the US East Coast. This can present problems if your shipping company wants the tank to be empty: ours did, of course, and apparently so do all the others.
2. US Customs in Baltimore requires that the RV arrive at the port in time to allow four full working days before departure. At least that's what our agent told us to explain why our RV had been bumped from the ship departing on August 11. Up until then, the most she'd said was "Oh, the shippers like to have it there four days before." (Note the difference between "US Customs requires" and "the shippers like to.") She also asked,"Can you get it there tomorrow?" Not "If you don't get it to through customs in Baltimore tomorrow it will be bumped from the ship sailing on August ll." We didn't, and it was.
3. The RV books you read beforehand tell you that Europe uses lots of different electrical plugs so you should buy lots of adaptors. But they don't tell you that no matter how many adaptors you buy, it isn't enough. We waited until we'd arrived at a campground in Belgium before we bought a looong extension cord designed to handle the European standard 220/240 volts, and its male plug fit the campground's female shore power outlet just fine. But when we got to campgrounds #2 and #3, one in Belgium and the other in the Netherlands, we had to borrow adaptors that fit yet another plug (they called it "European," as if it were the only kind around).
(Update, after 6 weeks: except for that first Belgian campground and a French one much later, everyone has used the "European" plug: Netherlands, Belgium, Luxembourg, France, and Basel, Switzerland.)
4. So you shell out another €12 for yet another adaptor. Because this one has only two pins, one at 3 o'clock and the other at 9 o'clock, with grounding plates (but no pin) at 12 o'clock and 6 o'clock, you have a choice of two ways to plug it into the female receptical. They tell you it doesn't matter which way you do it; they don't tell you that if you do it one way, your circuit tester reads "Hot/Neutral Reversed," which is Clearly Not A Good Thing, while if you do it the other way, all three of the circuit tester's lights come on--a condition that is not even listed among the six options on the back of your tester. So far, we've elected the latter option, with no ill effects, except on our peace of mind. (And, to be fair, at most of the campgrounds, reversing the way we plug in our adaptor makes the circuit tester happy.)
5. Well, maybe someone did tell us this one at some point...but if so, it wasn't nearly emphatic enough: buy your guidebooks before you get to Europe.
Cost of Lonely Planet's France guide in the U.S.: $24.99. Cost in a French bookstore in Luxembourg city: €32.35, or about $48.00! Cost of Lonely Planet's Belgium/Luxembourg guide in the U.S.: $21.99. Cost in the same #*&! Luxembourg bookstore: €25.95, or about $38.00.
6. And yes, I'm pretty sure someone told us this one, too...but again, not nearly loudly enough: when you enter Switzerland on a motorway (like one of the US's interstates), you get stopped at the border by an oh-so-polite, ever-so-efficient Swiss officer and relieved of many Euros as your contribution to the upkeep of Switzerland's motorways. For us in our motorhome, and for the shortest duration available (seven days), it came to 25 Swiss francs (about €17)! The moral of the story: drive into Switzerland only if you plan to spend more than a couple of days there, and then be sure to drive all the hell over the place on motorways to get your money's worth.
7. French McDonalds have free WiFi. So you go in and order something just to show your gratitude, and you go online, only to find that you can't upload onto your OurTravelsWithRover website. For that matter, lots of "free WiFi" establishments won't let you upload to your website.