Just back from a week in Lima to visit wife's side of the family and introduce them to our 17 m.o. son. Last time to Peru was 2013. FWIW, kids under two fly free on domestic flights but international flights charge to have the child on the parents' laps. About 130 something dollars for the child on this flight. Definitely not a fun experience flying with a kid for about 9 hours.
Dollar is strong against Peru's Nuevo Sol, but it seems like there has been inflation. Things just cost more Soles.
Cab rides, on the other hand are not expensive. In 2008 a cab from the airport to Miraflores could be had for 45 nuevo soles, and that's just what we paid this trip. Of course a tourist can pay more. At the kiosks inside the airport a ride goes for over 100 soles. We stayed at our usual lodgings with innperu.com. They're inexpensive and have a good location but they've really let the maintenance slip. No room service but there are several levandarias just steps away from the building.
I paid a visit to Colin Post who writes Expat-chronicles and just sold Peru Reports. He's an American who spent time in Colombia and ended up in Peru married to a woman from Arequipa (Southern Peru, 2nd largest city in the country). Post has a business exporting Peruvian products like maca, cacao, & camu-camu.
We brought a suitcase of used clothing for the family but apparently the government doesn't like that. The customs forms asked about that, and we didn't declare anything. No problem, everything looked like we could wear it and we didn't over do it.
If you're traveling to Peru you'll pass through Jorge Chavez Airport. The baggage handlers are notorious for helping themselves to travelers' belongings. Be sure to use hard shell type baggage with a lock.