As both an agent and investor in real estate, I can personally and professionally attest the significant role that investment properties can play in developing a portfolio of supplemental income.

But ultimately, I'd like to supplement my salary and escape the rat race.

I am still active duty military and investing heavily on my time off in an attempt for my passive real estate income to supplement my military income at retirement.  

I am extremely interested in real estate investing, especially the HOLD strategy as a way to supplement income for now.

I'm currently a page designer for our newspaper, but I'm looking into real estate investment as a supplement to my income (better than just letting the markets handle my 401(k), I figure) and maybe a way to becoming my own boss one day.

These make great supplemental comps and may end of being what you use if the others you picked out visually bust out.After I have my list I try to make sure they have the same bedroom count, within 10% of the sf^2 and within 5 years of age of the subject. 

I got a package containing a manual, some supplemental books with links to Internet resources, an audio CD and the account/password to their private-access Website (deal submission online form and other resources, such as basic real estate contracts in PDF format).

Ultimately I would like to 1031 exchange for a nice-sized apartment complex somewhere to supplement my retirement income from the Navy by the time retirement hits in the next 15 years.

There are many reasons but just to list few - economy of scale (more scalable, all the expenses will spread over a larger amount of the units), financing you can get a commercial loan with many advantages (assumable, options for supplemental loans ..etc).

I am working full time in San Diego and buying rentals now to supplement my retirement.