Leave Benson's apartment and head to your old office inside California Fire and Life.
Check the folder on top of your desk and point to the latitude and longitute written on the top right corner of the blueprint and the dependent valuation on the pink slip. A cutscene will play afterwards.
After the cutscene you'll immediately be in the Hall of Records. Speak to the guard sitting at the front desk, then head up and follow the land registry sign, then speak to the man sitting at the desk.
Follow the receptionist and interact with the S aisle. Inside the ledger look for the Suburban Redevelopment Fund, it's on the 4th page, and point to C.Sheldon.
When you're looking for the lot, enter the number that Kelso will say. Latitude is 34 degrees, 4 minutes and 29 seconds; the Longitude is 118 degrees. 17 minutes and 59 seconds.
On the calculator enter 1876988 then divide it by 90,000 to get lot number 20. Now head for the U section, second row from the back, left side.
Look for the land number on the ledger a gun fight will play afterwards. Kill the guys and watch another cutscene play. Yes, there's a lot of cutscenes from here until the end.
After the cutscene get in your car and head for Leland Monroe's mansion. Fight your way inside his mansion and head for his office.
Behind his desk there's a photo of the members of the Suburban Redevelopment fund.
Now turn right and open the safe that Monroe was crouching at earlier. Check the folder and read the document inside, then look at the shares certificate as well as a small notebook with Monroe's payroll inside.
Lastly there's a folder on top of Monroe's desk where you'll find a list of the people who refused to sell their lands.