Expert travelers know to check up on local tipping customs before they head abroad. It’s good to know, for instance, that waiters in Germany appreciate a 5 to 10 percent tip delivered by hand, while luggage porters in Israel should get 6 shekels (around $1.55 USD) per bag. If you’re in Hong Kong, make sure to round up to the nearest dollar on your cab ride. And if you’re dining out in Japan, don’t tip under any circumstances—unless offending a Japanese waiter is part of your itinerary.

But what about services that take place outside the typical tourist confines of hotels, restaurants, and taxis? You don’t want to stiff a helpful attendant, after all, or offend a local tour guide. Here are a few tipping occasions from around the world.

1. CAR GUARDS IN SOUTH AFRICA

Looking for a parking space in Capetown or Johannesburg? You’ll probably have to negotiate with one of the city’s car guards. These mostly unofficial workers help motorists find spaces along packed streets, and promise to watch over the vehicle in exchange for a tip, typically in the range of 2 to 5 Rand (around $0.14 to $0.34 USD). Due to the country’s high unemployment and crime rate, car guards can be a hit-or-miss enterprise. Locals claim they’re an annoyance, while travelers relate stories of their cars being vandalized by guards. Though officials say they’re trying to better regulate the industry, it’s best to use your discretion. If you happen to park on Harrington Street in Capetown, you’ve got nothing to worry about: Nunchuk-wielding car guard Master Lolo’s got you covered.

2. DOCTORS IN HUNGARY

No traveler plans on getting sick abroad, but if you’re headed to Hungary you might want to have an envelope of cash on hand just in case. Locals, expats, and visitors alike say doctors often expect a tip in exchange for their services. A visit to a general practitioner might warrant 3000 HUF (around $10.50 USD) while a specialist may be expecting 15,000 to 20,000 HUF (around $52 to $69 USD). The practice started during Hungary’s Communist era, when healthcare workers were criminally underpaid, and still persists today. Some travel guides say the practice is going by the wayside, while others claim it’s still widespread. A 2013 study showed patients pay a total of $162 million USD annually to practitioners.

3. SHOE MINDERS IN SRI LANKA

Drew Leavy, Flickr // CC BY-NC-ND 2.0

Temples throughout Sri Lanka are open to visitors curious about the country’s architecture and religious customs. To get in, though, you’ll need to follow proper decorum and remove your shoes. There’s usually an attendant who keeps watch, and according to Allison Sodha of Sodha Travel, it’s customary to tip these individuals between 10 and 20 Sri Lankan Rupees (around $0.15 to $0.30 USD) before leaving. And if you’re lucky enough to have a monk show you around the grounds, it’s customary (not to mention good karma) to leave 100 Rupees (around $1.50 USD) in the temple’s donation box.

4. PORTERS ON PERU’S INCA TRAIL

Hikers who want to journey up to Machu Picchu on this famous (and difficult) trail are required to book in advance through a licensed trekking company. The arrangements include porters to haul all your gear, a licensed guide, and, depending on the size of the group, a cook and an assistant guide, as well. You’ll no doubt be grateful for the assistance, so why not show it? Trekking companies recommend tipping porters an extra 50 to 60 soles (around $15 to $18 USD) for the trip, and anywhere from 50 to 100 soles (around $15 to $30 USD) for the guide and cook.

5. GAS STATION ATTENDANTS IN MEXICO

All Pemex gas stations in Mexico are staffed by attendants who will fill up your tank, wipe down your windshield, and maybe even check your oil and tire pressure. Due to low wages — typically less than $5 a day — these workers rely on tips, so 5 to 10 pesos (around $0.29 to $0.60 USD) is customary and appreciated, with a few more pesos warranted if the attendant goes above the call of duty. Since state-owned Pemex is the country’s only fueling company, there’s no need to search out the lowest price while you’re on the road. But beware of scams at the pump, including overcharging and falsely claiming a credit card is declined.

6. YACHT CREWS

Travel doesn’t get much grander than having your own private yacht. A good crew will chart a scenic course and ply you with plenty of food and booze. And in return, they deserve a generous tip, typically in the range of 5 to 15 percent of the total trip, according to the Mediterranean Yacht Brokers Association. Tipping each crewmember separately is one option, though experts warn that it’s easy to overlook less-visible workers. The best bet is to put the money in an envelope and give it to the captain at the end of the trip.

All images courtesy of iStock unless otherwise noted.