I've started to do a bit of shopping on the BHW marketplace for links and other SEO services for my website. There are hundreds of posters advertising their services with tons of reviews from other BHW users so it gets a bit tough deciding which ones are worth spending the money on. For someone just starting to dip their feet into buying these services, what should I be looking for? How should I filter good services from the bad? What kind of advice would you give me?