There is no single location to enter "closing costs" for a refinance of a rental property - where they are entered depends on what the closing costs are.
Some costs listed on a closing statement ("closing costs") may be deductible in the current year (e.g. prepaid interest and real estate taxes), some must be capitalized and amortized over time (e.g. points) and others added to the cost basis of the property (e.g. like title search fees or recording fees) and depreciated.
These "costs" are entered in their appropriate sections of the Rental Properties and Royalties interview of TurboTax Self-Employed (or desktop Home & Business).
See What can I deduct when refinancing rental property?
