You can use all the transferable skills that you acquired during your MPH like Leadership, research, patience, courtesy, caring about others, typing skills if u learnt during MPH, teaching, time management, team work, familiarity with U.S. Education system and learning.
You can get easy opportunity to do research, observership, and finish Step 2CS and Step 3 more peacefully.
Getting a credit card: I got Citicard a few months into my MPH first semester and it helped me tremendously as I never had to think about cash. It was painful to pay back credit at the end of each month though.
It is costly. I had to spend around $30K to finish my MPH. Probably, you could do it for $10K if you already finished steps 1 and 2 prior to starting MPH.
It is time taking. If you are in your home country, you have to take GRE and TOEFL to come to America to do MPH. This takes several months. Doing actual course takes anywhere from 18 months to 2 years. Due to thus time, your year of graduation may be increasing.