Good spelling and grammar is free. The same advertisement will cost you the same price with or without spelling mistakes. Professionalism and good grammar is key to online and offline advertising.
With spell checkers built-in to all modern software there is no excuse for bad spelling. I spotted this spelling mistake on a branded company vehicle in traffic during the last week. A vehicle wrap costs a lot of money and this mistake really detracts from the brand image. Even with “free” online and social marketing spelling mistakes will damage your brand.