What to search for when looking for a guest post provider ?

What do you look out for when deciding to add a guest post site to a guest post website

in order that you do not end with a google penalty ?

Honestly price is probably one of the best indicators. You cannot get a legitimate guest post cheap. There is a lot of work involved and nobody would waste their time finding a blog, contacting the owner, writing content and guaranteed submission for a cheap price. Some of the "guest post" services will create nice looking links but the websites tend to be flooded with nothing but posts with external links.

I would love to find a reliable guest post service but I feel like the actual price of these links will scare most people away. There are some strong link building services in the BST section but you will be paying $100+ for one link.