They pay a flat monthly rent rate that includes utilities but they also have a monthly (and mandatory) "house contribution" that is paid at the same time as their rent.

Also, Ensure that you've negotiated a flat fee for selling, it's insanely easy to sell these days with the market roaring.

I have had good luck with local Facebook job ads too but I had to do a bunch of screening calling references. 

A few day layovers due to weather not allowing stuff to dry or your guy had a flat tire on his van, fine, don't care.

I’d like to find a large house with a granny flat ( that we would live in).

We definitely know TENANT SCREENING is one of the most important factors in making this work!

Last July, my fiancé, now wife bought a 2 flat that was advertised as a SFH and the zoning certificate says SFH, but it was built as a two flat. 4 entrances, 2 baths, 2 kitchens, 2 furnaces two 1960’s mailbox slots in the brick etc.

Or is it flat with lots of cash flow?  

We currently have a realtor to do the grunt work of finding and screening tenant applications and then we self manage.

Screen them the same way, do scheduled property inspections and you should have a good experience.