Best to worst. 

@Neal PatelRecommend exploring as many sources as possible to get referrals AND cross-reference them to get as much accurate information as possible.Check out NARPM.com, BP’s Property Manager Finder, etc.Also, encourage you to learn from the mistakes of others - by reading posts here on BiggerPockets about owners not having their expectations met by their current Property Management Company.

Never, Never use your sellers property tax expenses to estimate your future property tax, this is a big mistake done my many people in the industry.If you haven’t sell your Main home where you are living yet you might consider to keep it, because your new home would be triple the amount your are paying right now.

Too many investors make the mistake of trying to treat it like a short-term rental, which is a great way to get yourself into a bind.You can keep more than one security deposit in the same bank account, but it should be held separate from any of your own money.You need two accounts: checking and savings.

Biggest mistake of my life was not keeping 50 more of the 500 or so I flipped, HUGE mistake. 

the worst thing you could do would be to buy a bad deal.

Facebook groups are the worst.

We have 8 business entities availing of their services, and as "advisors", they should make business life easier -- not add more work on your plate --- but instead, my team and I have been checking for mistakes, or following up on action items, missed deadlines, and paying penalties to the IRS and Secretaries of State due to their negligence.

@Benjamin ColemanRecommend exploring as many sources as possible to get referrals AND cross-reference them to get as much accurate information as possible.Check out NARPM.com, BP’s Property Manager Finder (BiggerPockets: The Real Estate Investing Social Network), etc.Also, encourage you to learn from the mistakes of others - by reading posts here on BiggerPockets about owners not having their expectations met by their current Property Management Company.

@Max Emory I can pay it off within a year with just cashflow from all rentals combined but worst case, I am saving too..