I do not know the answer though, wether you can roll over a note to ine?

Have a rollover-IRA from prior 10+ years of employment parked at Vanguard.

I'm certain you will be offered an option to do the rollover into an IRA or roll the funds into new company plan.

Yes, if those investments are simply conventional market based holding in a prior employer retirement plan, you can rollover to a self-directed IRA or Solo 401(k). 

They do not typically hold any cash other than for brief periods when you may be moving funds into or out of the structure at the IRA layer like with a contribution, distribution, or plan-to-plan rollover. 

She was actually kinda pissed I didn't roll over and I wound up financing the difference, but got my price.

Those could be interest rates increased say on NY Prime or some index.You could also roll over the loan with an interest rate adjustment, additional reduction of debt or both.

Jeff, The issue I am facing with is due to the amount of time it will take to roll the funds from my existing ex-employer's 401k plan to a new solo-401k plan which I was hoping to use to fund this property.To give you an example, let's say this property is contracted for 300K.Let's say I have one IRA account with TDAmeritrade say with 100K, Schwab with 100K and a 401K plan with JP Morgan with 500K.Previously I had inquired with TDAmeritrade, Schwab, and JP Morgan and they all told me all it takes to roll over to another IRA provider is 3-5 days. 

You can roll over the gain from one piece of investment real estate to another to another and another.

The mechanics of it is we roll over 401k funds from a work 401k and start a personally-directed 401k.