Hi Monique,
Only few suggestions.
Land has to be an asset in company's balance sheet too because over the years, it will give you the profit.
Else,
if it just for the expense then its better to create WBS as LAND and SUB WBS as Overhead Expenses, then just capture the actual/direct cost on those WBS including the expenses prior to purchase of this land.
Else,
If you think that in future it will be part of company's balance sheet, then go as per Sammar's suggestions.
Regards,
Amit.