After about 7 weeks of searching, I've finally managed to rent an apartment in Mexico City. And I'm here to help you do the same...if you're so inclined.
It's surprisingly difficult to find any information in English about renting an apartment in Mexico City on the Internet, so I'll do my best to lay it out for you as thoroughly as possible.
There are a few websites geared toward apartment rentals here, but most of them are pretty bunk. That being said, they are still the best resource for getting an idea of prices if your Spanish isn't that sharp.
Here's a list (with descriptions) of the sites that I suggest using:
1) Dada Room - This is probably the easiest way to find a room to rent in Mexico City. It works as a middleman to bring together people who have rooms for rent, and people who want to rent a room. Most of the rooms available are in nicer areas of the city (Condesa, del Valle, Narvarte, Napoles, Roma Sur/Norte). If you're alone and just want to rent a simple room in a nice apartment for 6 months or so, this is the best site to do it with.
However, if you prefer living by yourself or with a roommate that you know, this site has nothing for you. Another downside is that the rooms are a bit overpriced (hardly anything less than $270 USD).
2) Vivanuncios- Vivanucios is a place to look if you want to rent your own private apartment in Mexico City. The site is good in the sense that it has numerous listings that you can refine by price, neighbourhood, number of bedrooms, furnished/not furnished etc. Unfortunately, the response rate is horrendous. Out of probably 15 inquires (both email and phone) I received two responses - and one of them was a money wire transfer scam. The site is worth a look if you want to rent something longterm in Mexico City, but I didn't have much luck with it.
3) Segundamano - Segundamano is very similar to Vivanuncios, and unfortunately my experience with it was similar as well. Response rates are low, it is not scam-free, and many places will require a cosigner (someone who owns their own property in the city and is willing to vouch for you). However, like Vivanuncios, it is still a good place to get an idea of what prices you should be paying in what neighbourhoods. Worth a look, but hardly anybody got back to me with inquiry responses.
4) CompartoDepa - CompartoDepa is kind of a strange site. First of all, you need to sign up before using it (which I hate doing) and there are hardly any listings. Like Dada Room, the site is designed to pair you up with people who have rooms for rent. Basically, you set up a profile, and you message people or people message you about rooms for rent. Many of the rooms aren't in ideal locations, and some of them are little more than hostel dormitory-looking things. On the upside, I had a lot of people offer me rooms through email, but I didn't have any interest in them. I wouldn't suggest using this site unless it's a last resort.
5) Roomies-Roommates DF (Facebook Page)- This is an adequate resource for finding a roommate in Mexico City. Essentially just a Facebook page of rooms for rent in different areas. You can request more information through comments, private messages, or by making a post of your own. The page seems rather trustworthy, but there was a warning about a guy that was scamming people by pretending to rent apartments that weren't his. Another good site if you're just looking for a room to rent in a house or an apartment. Some advice: if you are a foreigner, say so and post in English. I received way more responses and interest in renting to me when I did this.
6) Casas.Trovit- Again, a very similar site to Vivanuncios and Segundamano. Same prices, slightly better response rates, and I didn't encounter any scam attempts. The site is kind of like Skyscanner for apartments: it draws listings from multiple sites into your search results. I was actually able to arrange a viewing using this site, but by the time I arrived to see the apartment the next day, it was already rented and someone was moving in. The one downside of this site is that I found it slightly annoying to navigate - There aren't as many search filters and it's sometimes difficult to discern locations, how recent the listings are etc. Still, worth checking out.
7) Airbnb- Chances are that if you're a traveller, you're already familiar with how Airbnb works, so I'll save myself some time and spare you the details. Here in Mexico City, renting an apartment through Airbnb will usually be more expensive, and more often than not you'll have to share with the owner of the place. However, if you have a high budget you can find some really nice private rentals (short and long term) in good areas. If you want to share a place with 3 or 4 people for a couple months, or have a budget of about $30 a night and up, definitely consider using Airbnb to find an apartment in Mexico.
8) Craigslist- You definitely all know how Craigslist works. Unfortunately, it hasn't really caught on here, so you won't find many listings, and the ones you will find will usually be overpriced because they will be geared toward foreigners (most listings will be in Condesa, Roma or Polanco). However, because most apartment rental ads on Craigslist are aimed at foreigners, the process is usually much more straightforward and much more secure; the person renting the apartment is more likely to speak English or be a foreigner themselves, and usually won't require things like cosigners or references as long as you can prove that you can pay for the apartment for the duration of the rental term. I suggest using Craigslist if you have your heart set on living in a ritzier area, if you have a higher budget, and if you want to avoid the headaches and language barriers sometimes associated with renting through the aforementioned sites.
9) Walk around the neighbourhood you want to live in, and look for rental signs- Hands down the most effective way to find an apartment in Mexico City, but also the most intimidating if you don't speak very good Spanish. I dedicated two days to this, but the apartments were all either out of my price range, or already rented. If you have a friend that speaks Spanish, take them with you. If you persevere, you will definitely be able to find a place this way within a few weeks.
So, How Did I Find An Apartment To Rent In Mexico City?
The first thing I did upon arriving was find a cheap Airbnb place to stay at for a month to use as a base while I looked for something else. Fortunately, I was staying with a roommate, so we were able to rent a tiny house for around $240 USD each. Then, I hit the websites. Since we wanted to live together, and our budget wasn't huge (under $650 USD between the two of us), using sites like DadaRoom and Roomies-Roommates DF were ineffective. For the first two weeks, we called and emailed listings on the other websites I've mentioned, but most of the time we didn't receive a response, or were told the listings were taken.
Then, we hit the streets.
We were fortunate enough to have a local friend who walked around with us and called every listing we saw. Unfortunately, most of them were out of our price range (we were looking in Roma and Zona Rosa).
With only 4 days left in our place, we were running out of time. My roommate decided to check Craigslist as a last resort (we were told not to use it because it'd be too expensive). To our surprise, we found a fully-furnish apartment close to Condesa for about $500 USD. So we called the guy, arranged a meeting the next day and, after looking over the contract, agreed to take it.
I'll admit we were lucky - if we didn't find this place I'm not sure what we would have done for the next month. Also, the guy seemed to prefer to rent to foreigners, and I'm sure that helped our case.
If I were to offer one piece of advice for someone trying to rent an apartment in Mexico City, it would be to never give up. It can be somewhat of a harrowing process compared to renting in Canadian, American and many European cities, but as long as you are firm with what you want, are cautious of tricksters, and persevere, you'll find something eventually.
If you have any questions about renting an apartment here in Mexico, post them in the comments below and I'll do my best to answer them!
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