I'm looking to contact blog owners manually and asking them if I can guest post on their blog. The problem I dont know how much a guest post is worth. I saw a few BST here but I'm sure if I contact the owners individually I should get a better deal. I wanted to know how to gauge the monetary value of a guest post? For example how much should a PR4, DA 33,PA 42 link cost? Is there any factors to keep in mind while buying such posts?