Since 2010, when the now 27-year-old made his debut for Renault (now Lotus) before switching to Caterham this season, Petrov has funded his race seats through private backing and sponsorship.
But his manager Oksana Kosachenko warned that they may change direction for 2013.
"If the presence of a Russian driver in formula one will be interesting to no one else but Vitaly Petrov and Oksana Kosachenko, we'll find what to do outside the grand prix," she told Sport-Express.
"Formula one is great and very prestigious, but for Vitaly it's a job that brings no money. Why? There are many reasons.
"In Russia, it's difficult to sell an athlete, but to sell a formula one driver is almost impossible," added Kosachenko.