See Section 1.266-1(b) with respect to capitalizing expenses.
https://www.law.cornell.edu/cfr/text/26/1.266-1
Note that the expenses must be otherwise deductible in order for the Section 266 election to be made.
If you held your property out for rent (e.g., would accept a renter, regardless), then the ordinary expenses you incurred would be deductible. If the case were otherwise, then the expenses are neither deductible nor can they be added to your basis via a Section 266 election.
