Where in the US can you make the most money fixing houses or buying rental property?
When you find the answers.....LET ME KNOW!!
In all honesty, the term "best" is hard to pinpoint. What you need to determine is what is "best for you." Generally speaking, newer investors see more opportunity and room for expansion when investing in cash flowing areas. These areas are typically found in the South, and Midwest. As a newer investor, you can take the proceeds of your NOI to reinvest, and continue to grow your operations.
But.....If this was the only method there would be no successful RE investors in Los Angeles, San Francisco and New York; which obviously isn't true. In these markets people have to adjust, and this typically means investing for capital appreciation, development, or syndication; which are all great methods but a bit more advanced.
I see a lot rent rolls for clients investing in many different areas around the US. The best areas I believe to be are Philadelphia, Indianapolis, Kansas City and some areas surrounding Chicago.
Buy and hold - for me indiana has been excellent as well as Utah. Little higher prices in Utah.
I've also done well in Southern California for Buy and Hold, since the properties appreciate. At this point, however, the cost of entry is very high, and I don;t know if appreciation will continue at the same rate
Indiana is cash flow positive immediately, but doesn't appreciate in the long term as much- historically.