@Marcus Robert Well done on your investment prowess so far. A few things in response to what you wrote:
1. Some employers, (when you're 50+) 401k adoption agreements will allow you to do an "in-service-rollover". Basically you stay working there and rollover funds into another qualified plan. Check with the plan administrator and use that verbiage.
2. 59.5 is when you can take distributions without penalty. As others have said there is no way for you to access those funds for personal use without taking a distribution which will be a taxable event...
3. When you transfer retirement funds into a self directed account you can certainly buy real estate with it. Something to consider is to convert the pre-tax funds/assets to Roth so you have tax free atm withdrawals at retirement. When you convert an asset to Roth you have to get a third party valuation and often they come in at a major discount..25-60% so your taxable amount is way lower than the actual conversion.
4. Educate yourself on the differences between checkbook control and custodial control. Also consider Checkbook IRA vs. Solo 401k. Some significant differences between the two.
Godspeed in this journey.