1. Underestimating the costs
The first thing to consider when looking for an apartment should always be, how much can you afford to spend. It's easy to look at the rent and consider your regular expenses (food, utilities, cable/internet, transportation, etc.), but there are other costs-especially in the first month -to consider.
For example, unless there is a specific move-in bonus, you will have to pay first and last months rent in the first month of moving in. There are also frequently costs associated with getting cable and/or internet activated when you move to a new place. If you have pets, many residences also require a pet deposit upon moving in, and if you require parking there is typically a monthly cost associated with that as well.
And if possible it's always best to have some money stored away for emergencies, so if you can try to budget and find a place where you don't have to empty your bank account.
2. Not seeing the apartment before moving in
It is always strongly recommended, and sometimes required, that you personally visit the apartment you plan on renting before signing a lease. Besides the obvious reason that pictures can sometimes be deceiving, you'll also want to try and get specific measurements of the doors and floors to ensure that any furniture you bring can actually fit where you need it to.
It's also a great chance to see the neighbourhood, and view the amenities in the building to ensure that they fit your needs.
Also worth checking when in your apartment is how many outlets and cable jacks there are, and where they are in the apartment. It would also be wise to check your cell phone to see what you reception is from inside the suite.
3. Not getting your priorities straight
Before you even begin your apartment hunt, make a list of your wants and your needs. Things that will be part of your day-to-day schedule, like your commute, access to grocery stores, cost of rent, and so on, should be considered a "need". Typically building amenities (gym, pool, etc.) and neighbourhood features (restaurants, entertainment, etc.) would be considered a "want".
4. Going without renter's insurance
It can be costly to repair damages and recover your belonging in case of a fire, flood or even toilet back flow. Tenant insurance will also cover you for any liabilities that you are responsible for such damages to your neighbours.
5. Forgetting basic items to make a home
If you've never lived on your own before, you're bound to be short a few essentials or forget some necessary items. For example, it's good to stock up on non-perishable foods to get your cupboards filled up as soon as you move in. You'll also want to make sure that you have a tool box, a flashlight and a first-aid kit for any emergencies that may come up.