Please share recommendations on where to buy basic furniture (sofa, chair, end tables, coffee tables, dressers for bedrooms,etc) that will last through the years but also be reasonable. 

I highly recommend you educate yourself on how to handle problems before the problem is a problem.

Then, contact an independent buyers agent and ask them for their recommendations on mortgage brokers that can find you the best assumable loan.

I did this a few years ago and it still looks good as new, but I recently read that its not recommended to use fix-it-all on the exterior of the home because it can absorb the moisture in the air and further rot the wood. 

Also, if eventually you get into that house hack, and elect to self managing a duplex, triplex or 4-plex that you own/live in, you will by default learn about property management skills and no license is required to manage the property you own.To answer your specific question, yes - you can become an employee of a property management company to learn about property management and I highly recommend it!

I'm setting up our basement apartment as an Airbnb and need a recommendation for a reliable cleaning service.

I would highly recommend them. 

I would not want to put the seller in a tough position either where they may lose out on other offers.What would the seasoned wholesalers in this community recommend?

Did you work with any real estate professionals (agents, lenders, etc.) that you'd recommend to others?

I would recommend no more than 4 for the first, just for the ease of financing and getting the best terms until you're more experienced in this area.