Trading over the phone is slightly more expensive but Peterson said most of its clients used the internet.
The service does not include any advice or research.
The cost of using full-service broking firms like Craigs Investment Partners or Forsyth Barr starts at around 1 to 1.5 per cent of the amount invested plus administration costs.
Des Hunt, a regular share investor and member of the Shareholders Association, said he used transaction-only services when he was comfortable with the amount of research and information he was able to gather on a company.
Beyond that he uses full-service brokers or fund managers to invest in a wider range of companies.
Hunt said he also believed in negotiating fees when it came to dealing with full service brokers.
"If you are doing enough business anything is negotiable."
Hunt said when choosing a brokerage firm or fund manager he looked at who was running the company and what their track record for investors was like.
Hunt also asks fund managers whether they will attend annual general meetings and how they would vote on certain resolutions.