You can learn more about the basics of prohibited transactions at the IRS website: https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-prohibited-transactions.UBIT is a tax that is levied on tax-advantaged accounts when they engage in (1) active business or (2) use leverage to finance deals.

He tells me his building is zoned for mixed use and approved for professionals with employees up to 3.

"Sale, exchange, or leasing of property between a plan and a disqualified person"RESOURCEShttps://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-prohibited-transactionshttps://www.irs.gov/irm/part4/irm_04-072-011.htmlhttps://www.irs.gov/retirement-plans/retirement-plan-investments-faqshttps://www.irs.gov/retirement-plans/retirement-plans-faqs-regarding-iras-investments

Dmitriy, if it is Roth 401k funds, and if they stem from employee contributions, then generally the 401k participant is still required to meet the one of the distribution triggering events. 

I'm ready to get into real estate investing full time, however, I've recently gone from being an employee to being self-employed.

Basically, you become the employer and the employee, which means you have to pay both sides of the social security and medicare taxes.

If you wanted to sell it you would need to build a business with employees and systems in place to handle all of the day to day tasks for there to be any value to a buyer.  

Hi everyone,I figure the best way to get the best advice would be to give a little background on my situation and see what everyone thinks.I am a new business owner and my girlfriend is a salaried employee.

Otherwise there are great possibilities, as either an employee or eventually owning your own business.

After that i would like to get a few rental properties for passive income and then move on to a few buy and holds and small flips.My current situation- I am a full time employee under the Dallas Mavericks umbrella doing sales.