I think you'll be fine in Peru with the lenses you've got. I took a 75-300 and 24-70 (plus 1.4x tele converter)and didn't feel like I missed any shots - other than the aerials of Nasca. If you're going to be shooting museums & churches you'll need faster lenses (some flash restrictions). Oh yeah, up in the high Andes, you'll want a uv/polarizer in bright sunlight. I had a grad density filter as well :)
ganjoa
BTW this was pre-DSLR film gear

Great shots of London!
What kind of lens setups were you using?

Hi Rich - this is more about shooting in Italy than lenses - but on my trips I did very heavy museum and artwork photography. In churches (the vatican) lighting is pretty low - faster lenses would've been better. If you're not going to do substantial inside shooting, by all means go with a 18-250 Sigma or 18-200 / 28-300 Nikon. I really like the Sigma 18-35 f/1.8 for inside detail work and other low light situations, but it's pricey.

I usually carry using a Badger Tactical rig which works great inside my overalls I wear around the farm. When I'm not in the mood to carry on my person, I keep my pistols in a "tankers bag" or purse, no apologies.

I'm kind of in the same boat regards being an old film guy. I don't think you can go wrong with any of the 24MP Nikons (7100,5300,5200,3200). I'm a big on using the brightest glass, so I haven't been "impressed" with the f/3.5 zooms Nikon offers in these kits EXCEPT in the 200-300 length lenses where f/3.5 is near top-end. I like the Nikon 28-300 for zoom range, but the 18-200 or Sigma's 18-250 make excellent "do everything" lenses as well. The 7100 with its' built-in motor lends more flexibility to third party lens choices, if you're into that. Good luck!