If it means you understand concepts but forget to carry the one when you're adding by hand, no problem - use a calculator or a computer program.

Look into FHA and NACA programs for low downpayent and financing assistance.

My biggest concern with people who buy all cash are those that literally spend ALL their cash and lose their cushion when it comes time to deal with major repairs, increased vacancy, job loss or prolonged illness. 

If you are a first-time home buyer, and you are not a high income earner (yet), call the city halls and/ or community development agencies of the cities that interest you and ask if they have any programs available for aspiring home owners.  

My agent got an email back from the listing agent basically threatening me with the loss of my earnest money if I don't cave in and pay the assessments like a good little boy.

Either way they are A paper programs and you are protected from up on high by over-governmental control.

I also have had some exposure to US Tax Lien Association programs and they are very aggressive.

I was also checking out @Ben Leybovich's CFFU program and it looks like I'll be investing in his program in the near future.

Finally, Please share wins and losses in low income areas.

Those programs that you see for sale on Facebook and the seminars, they cant run comps for you, they can't write contracts for you, they cant find buyer leads for you, and I'm pretty sure they cant find seller leads for you.