These are the books I recommend as intros to apartment investment, and with the exception of Frank’s cash flow book (and Peter’s) they’re pretty quick reads:
Frank Gallinelli's book on cash flow is the source for understanding income properties. You can find it on Amazon here: What Every Real Estate Investor Needs to Know About Cash Flow... And 36 Other Key Financial Measures http://amzn.to/Zv0Zph Frank and I don’t agree on everything but this book is the bible as far as I’m concerned.
Frank also has another book called '10 Commandments for Real Estate Investors' that I reread every other month or so as a reminder: http://amzn.to/15ikXL0
Ken McElroy has two great books on apartment investments and one on property management:
The ABCs of Real Estate Investing: The Secrets of Finding Hidden Profits Most Investors Misshttp://amzn.to/HdXVf1
The Advanced Guide to Real Estate Investing: How to Identify the Hottest Markets and Secure the Best Dealshttp://amzn.to/1bcWx50
The ABC's of Property Management: What You Need to Know to Maximize Your Money Nowhttp://amzn.to/1d518JK
People often mention Dave Lindahl’s books but I think Ken’s are better, one reason being that Ken is out there doing it and was dragged into the guru thing by Kiyosaki while Dave is mostly a guru who was mentored by Ron LeGrand, one of the old school gurus (who I worked for back in the day).
Also If you haven’t seen Ken's BP interview on Podcast 052: Buying Apartment Complexes, etc. here:
http://www.biggerpockets.com/renewsblog/2014/01/09/bp-podcast-052-raising-millions-ken-mcelroy-rich-dad/
Because running an apartment is as much of a business as it is a piece of real estate I typically recommend The E-Myth Revisited: Why Most Small Businesses Don't Work and What to Do About It by Michael E. Gerber http://amzn.to/1Bs4HEh Many people I talk to don’t understand that the difference between owning a business and owning a job is about building systems and Gerber does a great job of explaining it.
One other book I almost hate to recommend but do because it does a really good job with why a team is critical and who should be on it is The Real Book of Real Estate by Kiyosakihttp://amzn.to/13bv4AO It reads almost like he wrote it to make up for some of the others that came out under his name.
For a deeper dive Peter Linneman’s textbook Real Estate Finance and Investments: Risks and Opportunities, 3rd Edition http://amzn.to/10Jo5xR is Wharton MBA level knowledge served up by a guy not only started Wharton's real estate program and ran it for 30 plus years but he's done plenty of deals himself and now is chief economist at NAI/Global, one of the big international CRE brokerage firms. It's five hundred bucks, less than some guru's ‘bootcamp' but way more useful… and waay cheaper than a Wharton MBA too!
Good hunting-