What are your views of giving something away for free, or a reduced rate to get a link?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

• 
  Rob Morgan: Hello Everyone, ;
  
  Just thinking about link earning for a minute, and the various suggestions and ideas bouncing around the Internet at the moment to get those wonderful links to your site. There are lots of great ideas ranging from interviewing people, sponsoring events, creating info graphics etc....
  
  However, what is peoples view of giving something away for free, or a reduced rate to get a link.....
  
  Let me explain..
  
  Suppose you have an advertising portal where sellers of a product, lets say used cars, can upload their stock for say $99 a month. In terms of link building would it be ethical (as in Google won't slap your hand) if you offer key sellers (i.e those with a high domain authority site) to place their stock on your portal for free, or a reduced rate, in return for a back-link to the portal site.
  
  Maybe these could be marketed as "Premium Suppliers" who advertise for free (or some other kind of attractive meaning) but in return for a free upload and advertisement of stock they have to place a link, which would range from a banner, exact match keyword, partial match keyword, etc etc...on their site.
  
  Personally I don't see any issue with this as it's a mutual exchange of benefit which is not really different to other methods, and you are certainly not buying links. The only difference is you would be incentivising the website for a link...
  
  Maybe this could be called "link incentivisation"  ;I don't know....I guess there are lots of other associated ideas. For example I own an advanced driver training business and I am offering students at specific universities free road safety courses, although I need a link from their website (which is in the format of a competition) for students to enter...
  
  Thanks
  Rob
• 
  Cordelia Oxley: Not such a bad idea, but the problem comes when low-authority sites ask why they don't qualify for a free advert...
• 
  Rob Morgan: that will be unfortunate, although like with many things, there will be a criteria which we do not need to disclose to everyone who happens to ask....I guess
• 
  Rick Eliason: Rather than involving money in the deal (this goes into the grey area shrouding link buying) why not convince them to link in other ways?
  
  First of all it is in the seller's interest to get as much visibility and traffic to their listings. Therefore a little educating on how them linking to your site will improve your site visibility in the SEs and therefore footfall to their product listings.
  
  Secondly a direct link from their site to their product listings on your site will encourage more of their own traffic to visit the listings. This is good from a user-experience point of view as they are helping their own audience find what they are after.
  
  This means no money transfer hands and you are doing nothing wrong in Google's eyes. The advertiser will be happy as this extra education in how linking to you will help them help themselves while also benefiting you.
• 
  Rob Morgan: Valid comments +Rick Eliason  ; thank you. I do think it is more off white then grey as how would search engines know? that link could be there as we are a related business, or have provided such excellent content they want to link to them....If it was a spammy link site that would be a different story however...
• 
  Rick Eliason: Very true.
  
  Google is quite sophisticated in detecting paid links in some cases (I'm sure others will be able to outline some of the ways it can) but mostly you have to be worried about the competition reporting you. ;
  
  You're right though, chances of being caught are slim :)
• 
  Rob Morgan: Would have to put together a compelling reason why the link appeared on the site I guess....As long as they are not coming from spammy sites and as long as the linking to site is of high quality and a positive user experience, I cant see a problem..
   ;