If you want to keep your other assets protected, you'll need to have your bookkeeping and operations in such a way that prevents a good lawyer from piercing the "corporate veil" and claiming that it's all the same, you.

Should I make a separate account or just deposit the monthly rent to my bank account but separate the finances in the book keeping portion?

With 20 homes you should look into a professional management software that will do all the accounting and book keeping internally. 

(only halfway kidding) Then think about how disciplined you both are at keeping your bookkeeping straight.

And if you are stubborn and hold out past that, doing it yourself actually costs you money.Next milestone will be outsourcing the bookkeeping and check writing.

Did you consider hiring a bookkeeper to do the accounting work?

And she'll do payroll or bookkeeping as well if you need those services. 

I have a 2-member LLC here and I provide all of the Property Management and Accounting/Bookkeeping/Tax for the LLC.

3- for those who use a bookkeeper, what do you know now that you wish you would’ve known when starting the hiring process?

In my own law practice, I set aside two hours a week for bookkeeping.