Otherwise take your time and talk to several custodians/administrators and probably those that do all 3 and also invest in real estate. 

If you're self-employed, the Solo 401k will provide many benefits over a self-directed IRA: Compared to an IRA, Solo 401k contributions limits are roughly ten times higher.There is no custodial requirement for the 401k.You don't need the additional expense and administration of an LLC to have checkbook control.There is a built in-Roth component whereas IRAs are either traditional or Roth, not both.A spouse can also participate in the same Solo 401k plan.The Solo 401k has additional tax benefits over an IRA when investing into real estate using leverage.The penalties for prohibited transactions are less severe, though it's best not to utilize this benefit :)

Usually, public safety wins in these cases, but the NIMBYs  are loud and furious and have the Zoning Administrators on speed dial for protests. 

It costs more in terms of accounting and administrative costs  to set up an incorporated Ontario corporation. 

A long-term option is the get your hands on the P&Ls for every new listing that meets your investment criteria and create an ongoing database of operating expenses.

An HR Dept or plan administrator should be able to advise you.The co may be planning to terminate the plan entirely since a frozen plan still has costs attached.

@Andrew Lawhorn The administrator of the estate should be allowed to make the mortgage payments on the property.

Haven't zeroed in yet, or developed a database.    

I would guess it would be pro data based on the replacement property cost for each, but I’m throwing darts.BTW, your 15% calculation on $16k cap gains would be $2400, not $1600....small brain fart I know.

Offer to buy out the heirs (kin) legal interest in the property and start the probate Administration process yourself.