That site has been around for years, it used to be a lot more comprehensive and was a members only site.
I was a member and paid about £10 a month for about 3 months.
I gained a lot of knowledge from it, Steve Pavis ran one of the biggest window cleaning firms in the north and his knowledge has helped me no end.
I can still remember some good bullet points which helped me focus my business in the right direction.
The reason i paid is the site was updated every month with new info and it was very little money in terms of the knowledge gained.
Dave