I'm willing to pay ~$50 for SEO, PR5+ backlinks, & Articles on forums/blogs. I want to be able to get about 20 organic registrations to my free hosting site/day. I know hosting is very competitive but 20 sign-ups/day is not that much. I think this could easily be done with $50 and a view hours of online work.
yes,it is possible but it would take minimum 2 months and depends on seo strategy and as you know hosting competition is high in search engines so it would be tough but not impossible to rank famous keywords like free hosting or cheap hosting etc.
I would be able to help you get great results very quickly, but $50 would not pay for 1 link, let alone the time to post it. SEO is an investment, you have to believe in yourself and your idea enough to take the step to hiring a SEO expert that will be worthwhile. I started learning SEO 10 Years ago.. I know my experience speaks for itself, and the results of my work are all over the Top of Google