Can I trust cheaper web hosting that cost less than $2 per month ?

No. Do not trust any web hosting provider that can provide you a shared web hosting account that less than $2 per month. They are not reliable. Their cost is there. Normally they lease a server at more than $200 per month, the only way they can earn money is put more than 400 domains in a single server.

It means your website will share the same IP address with more than 400 websites. You will have more downtime and less support.

But some website hosting providers provide free or very less prices in the first several months and charge normally afterwards, it should be OK. This is only marketing tricky.