Do you make money from 'advertising' some of the merchants mentioned in your site?

Most of the time, no. The main criteria that I use for mentioning any webstore, or physical store, or any merchants, or any brands, in anywhere in my site is basically this - they must have something unique or useful to offer. I list them without even informing them that I am doing so. A very, very small handful provides some form of monetary returns for me, e.g. Amazon associate programme. I think there are less than 5 of such merchants and they didn't really give me any returns so far! Hahah!

Bottom line is that although money is not the motivation, it is certainly welcome. At least this contributes to the upkeep of this site, e.g. pay for hosting service and domain name.

Apart from the above, the only revenue source will be the Google Ads you see.