Huaquillas

Crossing from Ecuador to Peru used to be complicated and dangerous, and there were many scams. You will see horror stories on the Internet from years ago. Now, Ecuadorian and Peruvian border officials sit side by side in the same building.
From Huaquillas you can take a yellow taxi to the joint Ecuador-Peru migration office 15 min along the highway for $5 (Feb 2018). Your driver may tell you that the Peruvian taxis only take Peruvian soles and offer to exchange money at rip-off rates. Don't fall for it.
Line up first for to get into the building, and to be directed to a "Salida del Ecuador" desk. Then you have to queue a second time (inside the building) for an "Ingreso Al Peru" desk.
On your way out, look for the green-and-yellow sign that show the fixed-rate taxi fares to a dozen different destinations within Peru, e.g. US$10 or S/33 for the 20-30 min trip to Tumbes (Feb 2018). The drivers take either currency.
The emigration procedure is usually quick. On entrance to Ecuador you get a stamp in your passport. Onward tickets are seldom required and if so usually you can talk your way out of it.
In Huaquillas you have to cross the international bridge by foot. Either to catch a mototaxi on the Peruvian side to the emigration office or a taxi or bus on the Ecuadorian side to the emigration office.
Several bus companies have international lines between Guayaquil and Tumbes or further south. They wait at the immigration office. This saves a lot of hassle and is, in general, a cheaper way of crossing the border.

The town is quite small so you can walk most places. There are three-wheeled "tri-moto" cabs. However, like any place, you might want to stay off streets that are darker or where there is little foot traffic.

The little plaza in the middle of town is small but nice.

There is some shopping on the main street towards the Peruvian border, but not much. Agues Verdes on the Peruvian side has more. For more shopping, try Machala about an hour north.

• Aki

  address: Avenida Hualtaco at Tungurahua
  A clean, modern supermarket a few blocks north of downtown that offers many staples, both local and international brands: food, water, snacks, dairy, fruit, vegetables, toiletries, cooking items and more.

• Hotel Habanasur

  address: Avenida Tnte Cordovez and Santa Rosa
  A decent restaurant in a hotel. The breaded items (apanado) and ceviche are quite good.

• Asadero Criollo Galpón

  address: Avenida La Republica at Costa Rica
  A delicious little grilled chicken spot they have only a few dishes: rotisserie chicken, soup (with chicken feet and neck, so you may want to skip if that's not for you) plus rice, plantains and macaroni salad.

• Gran Hotel Hernancor

  address: Calle 1 de Mayo and Av. Hualtaco

• Hotel Habanasur

  address: Avenida Tnte Cordovez and Santa Rosa
  Small, clean rooms with cable TV and somewhat slow wifi. A decent restaurant too. Safe and inexpensive.

This border crossing is known for muggings and robberies, be very careful of your personal belongings and safety.

• Machala, a much bigger city about an hour north
• Tumbes, a popular Peruvian town about 20 km away
• Mancora, a Peruvian surf town a few hours away