Sold my duplex in 2019 after 19 years, lived on one side the required amout of time in the past five years, other side was 100 percent rental

I have listed the sale income on both the personal income side (total sales price) and business side (half the sales price). I expected capital gains taxes on both sides, but the calculated final tax I owe seems excessive at about  25 percent without including any deductions such as the price I paid originally or credits such as the $250,000 tax free capital gains on selling your main home.  I was expecting the tax rate to be about 15 percent overall after I get the $250,000 deduction on my personal side. TurboTax calculated depreciation for the rental side at $106,000, and even after that is added, this tax amount TurboTax calculated and rate still seems too high. Where I am going wrong, in entering the information or can the tax really be that high? I "made" less than $150,000 in income from retirement income and early withdrawals from my 401K account.