1. You don't need a PaaS. Who said you do? That's rubbish. 2. Heroku does not treat PHP as a first-class citizen.

You can set up a Digital Ocean VM for $5/month. I'm hosting my small apps on it and performance has been worth more than $5/month, IMO.

One of my apps is www.puphpet.com - you can configure your server via my GUI and launch a new DO instance fairly easily.