1. SEO is not a On-Off Switch
We had a client that after they signed up, the very next week they were looking for results and we were barely done with keyword research and mapping them out to the pages and working on the content and everything else. SEO is not like an on-off switch that you simply turn on. There is a lot of research going on. Set your client’s SEO expectations right and explain to them the process you will be going through, even at a very high-level in the beginning just to set the expectations correctly.
2. We need to fix the code
The site is not broken, why fix it? SEO consist of onpage and offpage SEO factors. And in onpage factors, there are some sites that are really whacked out in the code. This should not be a problem at all, but if it was not clear who will do the changes, or if there are extra charges for the changes, this can freak out clients and might even give the impression that you have a lot of hidden fees. Make clients know that changes have to be done and be clear in the beginning who will do the changes, is it the client? Their 3rd party designer/developer? Or you/your SEO company?
3. Keywords should be on the page
Some clients want to rank for a keywords that are not even on their pages, and sometimes even worse is aside from that is they do not have much words on the page at all. Sure GoogleBombs exist, but GoogleBombing is getting harder and harder to do it not impossible as their algorithm is getting better all the time. Tell the clients if you want to rank for it, talk about it on your web pages. If not, it will be very difficult to rank well for the keyword.
4. Be in the location you claim to be
I want to appear for searches in every city, on Google Maps! Google Maps results either within the maps itself, in Google One-Box or in Google Earth, all of these have address verifications. You have to verify you are there, aside from that, ranking within the maps results improve with citations from other websites mentioning your name/company name in the same address.
5. Your cannot just get links anywhere
Some clients specifically tell you where to get links, buying them etc. Some will go out themselves signing guestbooks and placing blog comments and creating forum post. Relevancy and trust are key elements. A good product or service with good content, making these popular, creating a buzz, making people talk about you is still one of the best ways to get links. If there is nothing to talk about by the mainstream online public, this does not mean SEO is impossible, but the client should be aware link building is not as easy as it sounds. It is really easy to get tons of links, but it is not easy to get links that make a significant effect on ranking.