1) For the 1st tier do each web 2.0 have to have 100% unique articles? cause I don't have the budget to buy articles. I planned to create like 20 web 2.0 properties and only one property will have 100% unique article while the others have spunned articles that are 60% unique. Can this still be effective? 2) Do each web 2.0 property have to have different anchor keywords? Do each property have to link to different pages on your main site?
I think spun articles are a kind of spam in Google eye..So, i would like to suggest you to go for fresh, unique and useful content for your visitors..And also keep in mind that you are writing something useful for your visitors not for a search engine...
Spun articles will not get proper benefit to your site from the link wheel. After Google updates it is advisable to avoid spun articles.
You'd want to use unique articles each time, but if you can't and will be using spun articles, make sure they are more than 50% unique and that they are still good quality. Yes, it's better that you use variations of your anchor keyword/target keyword, and not the same one each time. Hope that helps. Have a good day!
If you are spinning articles then make it readable at least so you have to recheck all the articles, it would help in link building, I think.
It is worthless and time consuming task and it does not help to imrove raning of any site for any keywords.