@Natasha Esguerra the easiest way is to put it in your purchase contract that the current landlord will deliver the smallest unit vacant on closing.

As always, believe none of what you hear and only half of what you see.

That's a lot of office and bathroom; and finished area, over half of the building.  

start by driving around areas in your town you would want to invest. find houses that look like they need work (bad roof, bad siding, long grass, etc) and look them up on the tax assessor website. try to get in touch with them (facebook, google, etc) and see if they want to sell. research rents and comps in the area and make sure your purchase price and after repair value will work as a cash flowing property. this is the cheapest and easiest way to start.

That's probably the easiest way. 

Such as, clever things that you've learned to save time, extract lead nuggets out of half a million old emails, best mail merge techniques (which Thunderbird might do, we'll see) etc.

My other half found this house on the first day it was posted and viewed it with my realtor within a few hours.

I have heard of half at least a dozen contractors getting overpaid and then ghosting their clients just this year.At this point, you just need to get done so I'd be calling daily and trying to get subcontractor information to keep pushing the work myself. 

My question is, with a job that has some flexibility, what income generating option is easiest to jump into as a beginner with some knowledge and experience in real estate investing?

Example if a half bath cost $6k to put in and you would see an additional $150 in rent, that would me your ROI would be 2.5% which is not very high.