Applying for a job through a recommendation / referral from a third party and providing summary of previous experience for the employer to consider.
As you can see from my resume enclosed, I have extensive work experience in [FIELD]. My work experience has helped me develop an ability to deal with [difficult customers], a valuable asset for [this field]. Through my experience as a [sales assistant], I have learnt to be customer oriented. I have found that courtesy and a smile will always win customers over.
letter of application,