Is there any online tool to check the price for a link, based on the pagerank of the site which supply the link? What is the going rate for a link from PR4 site?
Check this page http://www.linkvendor.com/seo-tools/linkvalue.html or this one http://www.text-link-ads.com/link_calculator.php
I'm not sure I would. They seem a tad high first of all (especially the Text Link Ads estimates!). Second of all, I couldn't get it to supply consistent results from Link Vendor. For example, a link from the root of my directory (http://www.after5webdesign.com/directory/index.php) was valued at $47, while a link from my software page (http://www.after5webdesign.com/software.html) was valued at $3.50. Both pages are PR 5 pages. The software page has 27 links (11 External) while the directory root has 70 (3 External).
no you can't, there is more factor than pagerank. Traffic can totally change the value of link regardless of page rank also, 1) position of link on page, 2) sitewide or not, 3) # of out going link, can change the value of link ( My personal favorite is link embedded in content, i am willing to pay double for that) out of those tools http://www.text-link-ads.com/link_calculator.php work the best for me, you can use that to estimate the ballpark value.
A link vault it's calculated so : PR + traffic +/- others criteria PR = PageRank traffic = the traffic recived by that websites A link with a PR0 (because the webmaster is stupid and use cookies for example) but with millions hits evey hite, how much is costing then?! 1 USD?!