People will come to you if you can generate good rankings - top 5. Top 3 is impressive. Not for something like 'new furniture for sale in Stoke', SEO's who quote long tail as their calling card rarely survive, or they work on £50/month and hope the client doesn't mind them doing nothing (just tweaking your keywords Mr)
However if you can show and rank decent (business producing) keywords .. then it's without doubt that you can succeed.
Look at what we've done for client X, ranking no'1 on DDDDDD DDDDDD keyword. - that's powerful.