Hoping to become proficient in wholesale deals to find a juicy 4 plex within the next year.

If it was to go further into underwriting they are usually proficient enough to know which deductions to count and will look at your cash flow more then your taxable income anyway. 

Now my primary skills are JavaScript / Python / PHP / SQL, Relational / Graph Data Modeling, API / Web application development, and I'm pretty proficient with excel and google sheets. 

Once you know what to look for and where you can get very proficient at using it.

I'm looking for an accountant who can help me with tax questions specific to landlording, including:Section 179 expensing, safe harbors, bonus depreciationWill most accountants be very familiar with these, or should I seek someone with proficiency specifically in real estate? 

Back to your questions - how do you become more proficient with MLS?

Once you are proficient you will be able to travel to the away markets and invest for much much cheaper.  

I took a course from Michael Blank and have gotten really proficient at underwriting deals using his Syndicated Deal Analyzer spreadsheet. 

The things I learn in closing deals with others will help me be more proficient in closing my own deals.

Callsign KS1C - I'm still proficient in Morse Code to about 30 words/minute.