When my children were little I travelled to Corfu with a mosquito net which I bought from a camping store, I think it was called Blacks. I altered the net by cutting it into the shape of a curtain and used velcro to hang it over the balcony door. This worked very well as an extra defence against the mossies. I used (and still use) the liquid plug in machines - best if left on all day. I found the net over the window worked better than it would have done over the bed as it protected the whole room. If you use the nets, they are pre-sprayed with repellent but if you use them several times, you need to spray them with more repellent.
The easiest way to avoid them when you are sleeping is to use the plug in and preferably stay somewhere with ac so that you can sleep with your windows closed.