On one of my WordPress sites I use twenty four plug-ins. Some people think I'm crazy and say they only use a maximum of between five and seven.
I've never had any bad experiences due to using so many but must confess that I only use quality, mostly premium plug-ins and a good hosting service provider. I'm a firm believer in the saying "Penny wise, pound foolish".
So if you are not sure of how many plug-ins your WordPress site can cope with then you may find this article rather interesting: http://www.wpbeginner.com/opinion/ho...-on-your-site/