In the Marketing Industry there is a lot of fake services, snake oil, and downright theft. We need to know about these in order to guide our clients.
There are good SEO Link Building services out there, but if you ever come across a client who is paying around $100 per backlink, or getting thousands of backlinks per month - then they are buying trash. They very well could be working with a deceitful SEO agency who has hacked several abandoned websites and are posting comments or pushing blog articles to low quality websites.
If a client is looking for SEO services they should start with our Listing Service. When it comes to marketing you should know how Backlinks Work to better understand the SEO value.
We too get these calls. Clients should hang up and waste no time.
Domain Listings (as the logo shows in the image below) sends an invoice in order to have a listing in their directory. The invoice and the company get the typical person to think this is for domain registration and if they do not pay it their website will go offline. There is no value in this service, if they are looking for Listing Services they should consider our 360 and Reputation Management plans.
Clients need to pay attention to who their domain host is and who their website host is. Many deceitful Domain Registrars will attempt to steal a domain from another registrar by sending an invoice to the customer to host the domain. When the invoice gets paid, they will transfer the domain registration to their service, creating customer confusion and most likely a less than optimal service.
Clients who have a blog on their website are very likely to receive solicitations to post a guest article on their website. In exchange for hosting the guest article, it is agreed that the article will contain a backlink to the company in order to also receive some type of SEO benefit. This is usually a pitch of "I'll scratch your back if you scratch mine". It is true, new content on our client's website is a small win, provided that it is quality, but the benefits are significantly unbalanced. The backlink in the article that goes to the person who reached out is easily over 10 times more valuable.
A message like this is typically:
Our talented team of writers are currently drafting unique content around the clock on all things home-related. Consequently, we like to dedicate a portion of our site's content to being published elsewhere, in effort to collaborate with companies within our niche.
Would you be open to us sending over an article draft that would be a fit for your site? It’d be free of charge and we'd welcome any suggestions/guidelines your site maintains around subject matter or style. And of course, you'd have final approval on what gets published.
The scam is that they downplay the value to themselves and do not offer to reciprocate in some type of link partnership. If it would be valuable to get a backlink from the company, the best play is to push an agreement on link exchange - articles on both websites with backlinks to each other.
We highly recommend the article: 
Backlinks that work to better understand the SEO value.
