Aparthotels, or stand-alone apartments with all the amenities of home are the mainstay of long-term and independent travelers in Santiago. They are scattered about the city, and many of them are independently run by owners who opt to rent out their apartments by the week or month rather than have long-term renters.
You should expect at a minimum: WiFi, fully-furnished, cable tv, and in-building laundry. There may or may not be a gym and/or a pool, but they're likely to be of questionable quality unless it's a set of aparthotels all together in a buiding dedicated to the same. What you lose in terms of someone to orient you to the city, you gain in being able to spread out and live like a king in your pretend new home.
Mar Del Plata 2171- Esquina Ri
Jose Victorino Lastarria 43-61
Av Pedro De Valdivia 150, piso 12
Avenida Vicuna Mackenna 35