Most new police officers in the UK's biggest force will come from its pool of volunteer special constables under a recruitment overhaul being considered.
Other applicants will come from its body of Police Community Support Officers, or have law and policing qualifications, under the plans.
The Metropolitan Police Authority (MPA) is being asked to endorse the new guidelines to help save up to £2 million for every 100 appointments.
Currently, police recruits receive 25 weeks of training regardless of previous qualifications and on-the-job experience. They are paid a salary of around £23,000 during their first two years.
The Met's new model would see most new applicants working for 18 months as volunteers, also receiving other training opportunities.
According to a paper being considered by the MPA, this would save up to £20,000 per appointment thanks to lower salary costs. "Each 100 appointments through the new model releases between £1.2m and £2m cash savings from salary costs, depending upon the mix," it says.
The force's recruitment method would also change from "generic, lengthy ongoing campaigns" to "discrete, time-limited recruitment campaigns".
"The proposal will result in significant cash savings, improve local service provision and provide participants with a range of transferable skills," the paper says.
Last year the Met recruited 2,000 new officers, taking its total complement to more than 31,000. But as public finances have came under pressure in recent months, scores of would-be constables have had their applications terminated.
The MPA paper says: "Applicants were informed of the benefits of joining the (special constabulary) in terms of developing transferable skills and improving their odds of success when police vacancies arose in the future."