They expected me to "roll over and settle".

I have a roll over IRA I would like to invest in real estate and am looking for advice concerning penalties and tax implications associated with using an IRA.  

I also have investments in IRA, rollover Roths, etc etc,  I am well covered in the market and have been doing quite well there. 

If you rollover into a SDIRA, then any profit would have the tax advantage of an IRA.

. - Rent raises do rollover !

That makes accessing the capital a little tougher -- you can't just sell and roll over the profits; you'll be doing a HELOC or cash-out refinance.

Please note that you are obligated to pay back their 401k (regardless of the performance of your real estate investment).Per the loan offset rules that went into effect with the 2018 Tax and Job Act: if you leave your job and the loan is current at the time you leave your job but then the loan goes into default because you left your job, you will have until your tax return deadline (including any timely filed extension) to make the loan current by depositing the outstanding balance into an IRA (and thereby avoid the taxes and penalties that would otherwise apply).If you are self-employed with no full-time employees & you can rollover the funds, you could set up a Solo 401k, rollover the funds and take a 401k loan from the Solo 401k.In this case, you would purchase the property with the proceeds of the loan.

Also, can I roll over my employers 401k to a self-directed IRA?

The RISKS with leverage, are when you have tenant roll-over, a bad market, have personal issues (lost job, etc...), this increases your RISK/LOSSES as well as increases your potential gains.  

That money is on a 5 year amortization so your payments will be high each month.When you leave employer you can roll over your 401k to a Solo 401k with checkbook control.