Costs & Money
The strength of the Peruvian Nuevo Sol (PEN) will make perhaps the biggest difference to foreign visitors, but even then Peru is, by regional and global standards, fairly inexpensive. The Nuevo Sol is an unstable currency and you should always check the exchange rate just before your trip. For that reason, I give prices in PEN with a rough estimate in USD. In 2022, $1 USD is worth about s/4 PEN. In some situations prices are quoted (and best paid for) in US dollars - see PEN & USD.
Cash & cards
Besides major hotels and restaurants, most places accept only cash. Bank fees for accepting credit or debit cards are very high in Peru, which discourages almost all small businesses. Even entrance fees for national parks and archeological sites are often only payable with cash. Be sure to always have enough cash on you to get through a few days.
• At the budget end (staying in hostels where the staff probably doesn’t speak English, eating out only at markets, walking and visiting mostly free sights), you can away with about $25 USD/person/day.
• A more average budget for most visitors (staying at standard hotels or B&Bs where the staff might speak English, eating out once a day, going to the full range of sights and taking taxis), would be around double that, at $50 USD/person/day.
• Double that again and $100/person/day buys a pretty high-end experience, with luxurious hotels where the staff speaks English, meals at the full range of restaurants and taking taxis or renting a car.
Note that traveling solo will probably raise any of these per-person-costs by at least a third for all except budget travelers.