With the tax reform changes that occurred for 2018, itemized deductions have been impacted in a couple of ways, so even if the itemized deductions entered into TurboTax total $30,486, there was more than likely a restriction that prevented the full amount from being deducted.

For instance, state and local taxes (SALT) are limited to $10,000 as an itemized deduction.  This means that if your property taxes, and state income or state sales taxes total more than $10,000, only $10,000 will be included as an itemized deduction on your return. In addition, there are new restrictions on mortgage interest as well as far as what and how much can be deducted. 

See more information on the SALT limitation below:

https://ttlc.intuit.com/replies/3302003