I am finding conflicting info elsewhere online. 

In my experience the basics for a functional RE based CRM are:Custom Fields for Data Objects (Leads, Prospects, Applications, Buildings, Units, etc...)A Screening Engine (background/credit checks, employment verification, etc)Online Rental Application (this should automatically run the application through screening)Ability to mass email/sms leads and tenants to provide informationSurveys/Inspection formsI've been building real estate CRM tools for years.

I'm diving into QuickBooks Online for the first time and could use some guidance.

Is there an online platform on which we can do this or do you track this in a excel sheet ? 

Making the connection in person is completely different from an online interaction.

BP offers free online videos and educational courses for you to watch and learn from.

I am going to have my tenant pay rent online directly into my new checking account.

Online videos on social media platforms, educating your clients about nuances in private lending, coming on a popular blog to help people with financing issues, and connecting with others in your industry that specialize in something else. 

I'm using QuickBooks Online.

I look online and attend meetups.