The random attack on seven residents of a Vancouver apartment building has many people wondering how safe their buildings are from intruders.

Jerome Bonneric, 33, is facing 12 assault charges in relation to Thursday's attack that hospitalized six of the seven victims. According to police he was visiting a friend in the building, but witnesses say the violent random attacks happened on several floors on the West End apartment block.

The new, high end towers, like those in Coal Harbour, have video entry phones, electronic security access, and 24-hour concierge staff in the lobby monitoring security cameras.

And if you get in the lobby of these buildings, you need a fob to get to your floor, and you can't access any others.

But in older buildings in other neighbourhoods like the West End, it is a different story. Residents like Ashlie Winson-Jones know they have to rely on their own wits to keep intruders from slipping in.

"For the most part you know it's just kind of lock and key, and each floor is accessible," says Winson-Jones.

And that means it is up to residents themselves to make sure nobody sneaks in as they are heading out.

Some building post warnings not to let other people in, but often it’s a judgment call made in an instant, say residents.

"Sometime you don't realize there is someone coming up behind you. You open the door and someone grabs it," one West End resident told CBC News.

"I think in general people are more likely to let people in if they don't look suspicious," said another.

Most of the time it comes down to common sense: don't buzz someone in if you are not expecting anyone, and ask questions if you see someone you don't recognize.

Others say being friendly is the cheapest and nicest way to increase security in your building.

"Know your neighbor and have a relationship with your neighbour. If you don't have that, you have nothing," said one resident.

With files from the CBC's Kirk Williams