can i implement VR using Unity without using Gear VR and DK2 and instead use a cheaper HMD?

I am making a final year project on Virtual Reality. On Unity, the tutorials are based using whole Samsung Gear VR and oculus rift. Now as I am doing this individually and at the college level, i cant afford to get these High end VR gears, and on unity website, the tutorials are shown with respective to the those former VR gear. So my questions is that i can learn this tutorial by implementing it on cheaper HMD and any regular Android Smartphone?How should I start and what changes should i do?

The cheapest option is cardboard with a phone that has a gyro (that’s not every android phone but there are some you can get used pretty cheap). Just look up the specs to see if it has a gyro.