For short term cash I would consider fix and flip t hat typically lets you specialize in a single type of real estate. 

The guy in the polo shirt sitting in the clean F 350 pickup  talking on the phone scheduling jobs and supplies is the "contractor " or  "business owner " .Where investors and homeowners have problems is when they find the employees or subcontractors and hire them to do work  thinking they will save money .

For a new construction project, should I consider multiplex units, apartments, or townhome style units?

I'd be happy to help you calculate this property out to the T but there are a ton of variables you need to answer first, mentioned above. 

SO MUCH BETTER (i.e. credible).To make it you don;t just be the first choice.

What type of life style do you want: urban, suburban, highrise, big yard and pool?  

@Eris T.

This investment style requires more day-to-day involvement and more legwork building a team etc, but gives you greater control and, if done very well (ie your agent finds you a good deal, your contractor does a great job in a timely manner and no weird surprises turn up etc) you can end up with higher returns than turnkey because you buy properties that need work and then 'force appreciation' by doing a rehab that results in a finished product that is worth more on the market than the sum of what you put into it.

It's not hard to do an adjustable rate mortgage, 2.5% above the 1 year T-Bill is fair and you can begin much lower, say 4%, this is a good way to get your seller to hold the note (if he can) with a longer amortization, 15, 20 years, no balloon.

@Eugene Kemp@Chris T.