They do this so that they can pivot their business easily in the future if they need to do it.In our industry good examples would be Zillow.com or Redfin.com. 

Is this something we can install now easily with the tenant in there? 

Make sure they use meter boxes with wide lids and yoke bars/setters so you can change the meter simply if it goes bad or pull it if your tenant doesn't pay (most have eyelets for locking it out but they are soft brass and easily cut).

(and, I'm glad I didn't wait to pay off my student loans, because it allowed me to get into RE investing at an excellent time, when rates were low, prices weren't astronomical, and properties still cashflowed easily)...In my opinion, house hacking is arguably THE best way for beginning RE investors to get started--it has MANY advantages over other RE investment strategies, and you'll get to learn all of the essential lessons of RE investing and property management that are critical to success in RE investing...house hack a property every 12 months using an owner-occupant mortgage, and in a few years, you can have a solid portfolio...Good luck out there!

Just depends on what you want to do. there are other investments other than rentals you could certainly go into private lending and that 400k which would be pretty liquid could easily earn you and additional 40k a year and as I said far more liquid than a rental .. but you do not have any write offs. 

I am telling you this based on experience, it can easily make your life hell for 6+ months.

If they are professional, they can explain this quickly and easily.

I don't have enough cash to outright buy but a loan should be easily affordable since I plan on renting it out to pay that off.

Because later, you can easily use it as your mailing list!

You haven't seen a lot talked about in regard to seller financing for many years as interest rates have been dropping and  buyers could easily get loans.