Business structure: anonymity, taxed $, and retirement $

Hi all! I am interested in starting my REI business to meet a few specifications & I'd like your input on what kind of structure would work best. I understand I'll need to talk with a CPA and attorney too. Thank you in advance.

My business would ideally be structured to:

1) Invest in notes and be structured so that if the property were acquired by the business through DIL or foreclosure, I could legally coordinate a remodel/resale even though i would not be "swinging hammers" personally. 

2) Protect my identity - because of the nature of my regular job, I do not want to do business under my own name. I won't get into it, but this part is extremely important, there must be a clear delineation between my existing (self-employed) business and my yet-to-form real estate investing business both in name and in structure. 

3) Be able to fund some investments through a retirement account like solo 401k AND fund some investments using after-tax money to begin replacing some of my income prior to retirement.

I'm self-employed in my existing (non-real estate) business with no employees, and so I will be investigating solo 401k. 

What kind of structure could accommodate these needs? 

Thanks again!