As a newbie, you will find out there is more crap coming down the line.

Hi, I recently bought the neighboring apartment (condo) next to the unit I currently own in Manhattan and I am looking to combine the two units.

HI Rachel,I would suggest that youDetermine the potential cash flow for renting the SRF and the side of the duplex you live inThen determine your living cost of each of theseUse all of these to figure out which combination nets the most for reinvestment You would be applying your living expenses as a cost to the overall portfolio of the two properties. 

In any rental, I am using a combination of several metrics to determine if the investment is something I am interested in.

Is there a way to combine option 1 and 2 with out getting to complicated?

Combine your experience with Bigger Pockets various resources: ebooks, blogs, forums, podcasts, webinars, colleagues, keyword alerts, an awards system, a learn section, informative people in many fields of real estate, and more.Consider spending 30 minutes for 30 consecutive days on Bigger Pockets.

I purchase it with a combination of cash and private money.

Sending good mailer's is a combination of art and science.  

All together I made a very small profit, about 8 000$ total after taxes (both properties combined).

Finding mentors is a combination of networking and providing worth.