(Read David Greene's BRRRR book) The resources provided here at BP are amazing but not always intuitive so explore every aspect of the website and learn how to use it.

I've used QB for years at my "day" job and it's almost as simple and intuitive as you can get and pretty cheap and it's still going to cost you some money.

We process our ACH through Intuit/QuickBooks but there are other ways (like your own bank). 

It is very intuitive.

I work with tax matters a lot (I managed a Liberty Tax Service office, I worked for Intuit as one of the Ask a Tax Expert agents supporting TurboTax users) and I still hate reading through the IRS stuff....

I was trying to look up zoning laws but the websites don't seem intuitive to me so sorry for asking a potentially obvious question!

For a new user, Avail or Buildium are pretty intuitive.

@Zac RogersIt depends on your available time and interest in self-managing the process.I am on the passive side, so my intuition would be to find 1-2 great syndicators for him to invest with.

To trust my intuition about what is desirable in a property, to be able to hold on to the property long term and let it grow in value, and to not discount land as an option.

It's not intuitive to use it for keeping track of rentals, so you have to put some time to learn it.