As a sole proprietor LLC, how do I go about getting a mortgage?

No more work for the CPA than if I was a sole proprietor.

What about working in the same career, but changing work status (employee to sole proprietor)? 

It chooses to be taxed as a sole proprietor and all activity of the property is reported on the personal tax return of the member.  

You can run a "Business" as a "sole Proprietor" I suspect what you mean is "when do I create a separate entity, like a corporation, for my business?" 

The business can make a profit sharing contribution the plan of 20% of your net-business income for a sole proprietor / pass through entity or 25% of your W-2 wages in a corporate environment. 

Go on the IRS website and obtain an EIN as a sole proprietor - free and instant.

It’s import to keep your finances for each ownership separate in order to preserve the protections offered by an LLC.I have a bank account in my name as a sole proprietor and owner of my house hack triplex.

We are a woman-owned contractor (wife sole-proprietor) though we are going to incorporate at some point maybe soon.

I use the same lawn service for my sole proprietor LLC and my personal residence, which I am house hacking.