Family contribution is always the best source of money if your parents can afford
Military HPSP will cover tuition, fees, books, and also give monthly stipend ~$2,000 (1 year of service for each year of tuition). $20,000 sign on bonus for a 4 year scholarship.
Military Financial assistance program will give $45,000 annual grant plus $2000 monthly stipend during residency. (1 year of service for each year of FAP plus an additional year of service tacked on)
Uniformed Services University is the military medical school with free tuition, fees, books, etc. and officer pay of ~$60,000 per year. Automatic 7 years of service obligation.
There are private loans and federal loans that are subsidized and unsubsidized, some will accrue interest upon disbursement, others will not need payment until after graduation. AAMC website has a lot of resources to read up on this.
Some schools have full ride scholarships like Ucla or Ucr... but they are merit based or require an obligation to serve in a certain community
Imo best way to finance through med school is having rich parents or a desire to serve in the military. Sorry I cant provide numbers like how much loans will cover, I'm going through it and figuring things out myself.