How I saved more than $400 on my Paris vacation before even leaving for the airport

Katie Little and Ali Montag

When it comes to vacations, every penny counts.

On a week-long vacation, travelers can spend more than a month's rent or mortgage, according to recent data. So as a 21-year-old who has only been out of college for a year, I approached booking my summer vacation with one goal in mind: not breaking the bank.

The plan was to head to Paris with my friend Katie Little (a former editor and reporter at CNBC). To stay budget conscious, we strategized ways to save on travel and hotels. Here's what worked for us.

Ali Montag | CNBC

Do your homework about flights

First up came tackling the big ticket item, flights.

To hunt for fares, I used Hopper, an app that "analyzes billions of flights," according to its website. It suggested both the best days to travel and the best times to purchase flights. If your plans are flexible, the app can show a range of days that might be cheaper than others to book tickets. Once you select a window when you want to go, it gives you notifications for the best time to purchase.

I started looking for flights a couple of months before I wanted to take the trip and watched prices on the app for a few weeks. I also checked other travel sites like Kayak, Google Flights and Expedia. Though some experts have nixed the idea that booking sites use your search history data to increase the fares you're interested in, I used an incognito window just in case.

I purchased flights about a month and a half in advance and chose ones that were to leave and return on Thursdays, avoiding what can be higher prices for weekend travel. As a trade-off, I did have to take two extra days off of work.

In total, I paid $1,041.86 including taxes and fees for economy class, round trip tickets from New York's JFK airport to Paris' Charles de Gaulle.

So was that a good price?

According to air travel data company Airlines Reporting Corp. (ARC), the average ticket price to fly from any airport in New York City to any airport in Paris this summer is $1,498.94. That number is based on all round trip tickets purchased via U.S. travel agencies this year for travel in June through August. It was based on data from 30,782 sales.

Charles Schmitt, who has been a travel agent for 20 years, and works at Classic Travel in New York, gives a similar estimate. If you are buying in advance, the average cost for a an economy flight during the summer time from New York to Paris can range from $1,100 to $1,400, he says.

Schmitt says prices can go much higher if you book at the last minute or when schools let out for summer vacation.

My travel buddy Katie didn't use an app, but found another trick to save money. After she booked her flights, she took a look at the website again later that day. The cost for a seat on her flight had fallen by nearly $100, so she called Delta. They refunded the difference on her card. Sometimes, it pays to pick up the phone.

My estimated savings on flights: $260 (based on a mid-range price comparison)

Ali Montag | CNBC

Efficiency over comfort

Then came finding a place to stay. Since we planned to be in Paris for a week, accommodations would be a big portion of our budget.

Hotels in Paris can range from 100 euros (about $114) a night per room, including taxes and fees, at a discount hotel chain, to 200 or 300 euros (about $228, and $342) a night per room for mid-range accommodation, says Schmitt.

Since we wouldn't be spending much time in our room, instead of a hotel, Katie and I decided to opt for the oh-so-glamorous hostel experience for most of the trip. We found hostels listed by price and user reviews on Hostelworld.

We also researched access to monuments, museums, cafes and subway stops by comparing the best-priced locations on a map. We planned to only walk or use the Metro all week. A pack of 10 tickets is $16.

We landed on a hostel for roughly 38 euros ($43) per person per night for four nights, which included coffee and pastries for breakfast.

For the last two nights, we decided to go with a little upgrade. We booked a two-bedroom Airbnb listed for $110 a night, $55 per person. After taxes and fees, the total for a night came out to $144.50, or $72.25 each per night. Although it was pricey, it was still less than the average cost for a discount hotel and had the perk of a kitchen to save on making coffee, tea and snacks at home.

Katie saved another few dollars using a discount from a friend's referral to the Airbnb app. This led us to an additional tip: tweet for help. When Katie entered the code for the discount, the website wasn't processing the request. So she tweeted Airbnb customer service and they responded and processed the information, saving us $40.

(In case you're wondering, both the hostel and the Airbnb turned out to be clean, safe and convenient.)

My estimated savings on accommodations: $160 (based on four nights of a discount hotel price comparison and two nights of a mid-range)

In total, these strategies helped me save an approximate $420 on my trip before I ever left my apartment.

Don't miss: The 30 best places to visit around the world that are worth the money

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