I have been looking into some of the online courses from The CE shop and other online portals to buy a course to get through my realtor licensing studies, but I am confused on which one is the best one.

Someone in my neighborhood was looking for an apartment with a total of five roommates  and since they seemed like a right fit at that time I moved forward,  they added another roommate later and now want to add another roommate as they are struggling to make payments.

Contractor payments, online orders, card swipes at home improvement stores, utility payments...

I know this is pretty obvious, but have you tried checking the Montgomery County property tax records or the property tax assessment records online for Silver Spring?

Quickbooks desktop is a way better version of the software than quickbooks online.

It would be a section 8 rental, the fair market rent for section 8 (hud gov site 2024) on that zone is 1200 for a 2 bedroom, since it's a duplex it has two units with 2 bdr so the total rent would be 2400 (both section 8 tenants).

(For example, I am in the 24% tax bracket, so I will really only be earning 76% of what I earn from the tenet.)Is there a resource online that has all the tax write-offs as a landlord?

Local county records, zillow, trulia, any other big online site like that, hud homes, hubzu, spark offer.

He was referred to me by a trusted local contact and also has good reviews online. 

You need to network and search online; you cannot get a list of wholesalers.Attend REA events in Detroit or search online for keywords like  "We buy houses Detroit" or Sell House fast Detroit" and call the companies that appear in the search.