The usual configuration when I operate mobile in my 2016 Honda CR-Z is an older Kenwood TH-D7A and a newer Kenwood TH-D74A, all running off of a three-port 12V extension outlet that includes a built-in voltmeter run to the ignition-switched 12V car outlet. The 'D7A is tucked in the sunglasses/iPod/cellphone shelf under the nav system and is connected to a Mobilinkd TNC and tuned to 144.390 MHz. The 'D74A is used for D-STAR, FM phone, and secondary digital operations (such as Winlink), and is attached to one of two arms of a dual-arm cellphone mount that fits in the cupholder. The other arm holds my Google Pixel, running Android and APRSdroid connected to one of the DC outlets. I use an NFC sticker and Trigger to foreground APRSdroid when I place the phone on the cell phone mount, and then APRSdroid connects over Bluetooth to the Mobilinkd. In the event that I do not want to use my cell phone, I can tune the 'D74A to the APRS frequency and start the TNC.
For antennas, I use a couple of dual-band low-profile magmount antennas. I can't remember who made them; they've been moving from car to car to car for about fifteen years. I would not be surprised if they are from MFJ Enterprises, though. The coax runs along the center console, along under the back cargo shelf, and then up and through the rear hatch and on the rear of the vehicle.
When pedestrian mobile, I either use the same Android phone running APRSdroid over WiFi and 4G with Project Fi (depending on where I am), or my Kenwood TH-D74A. I have been known to throw the 'D74A in a cupholder in my wife's car when I drive that somewhere too, or else just use the phone and the cellular network again.