Our kids decided to call our 2008 Toyota Sienna "Nessa" which is short for Vanessa... But it is time to upgrade the maps feature and make hands free calling much easier. I'm looking at options but would like to spend less than $1,200. Actually less than $900.

Here are some videos about the process via YouTube

This is the stereo shown in the video: https://www.crutchfield.com/p_130AV2550/Pioneer-AVH-2550NEX.html
https://www.pioneerelectronics.com/PUSA/Car/DVD+Receivers/AVH-2330NEX

Crutchfield says though:
Installation notes:
When you replace the factory radio, the factory navigation system won't work anymore.
If you plan to bypass the factory amp, we recommend replacing your vehicle's low-impedance speakers with standard 4-ohm aftermarket speakers to avoid damaging your new radio. If you want to keep your factory speakers, you'll need to add an aftermarket amplifier.
When you replace the factory radio, the factory DVD player will still work, but audio will only be available through the factory headphones.

Put a USB 3.0 outlet in the van? https://www.petreldata.com/product/hardwired-2-4-amp-usb-vehicle-power-adapter-with-in-line-fuse/

I've been looking at this head: https://www.amazon.com/Kenwood-DDX9707S-Capacitive-Multimedia-Receiver/dp/B085TP4FML/ref=sr_1_1?crid=2YZZVT8I6DZL6&keywords=kenwood+9707s&qid=1687586990&s=electronics&sprefix=kenwood+9707s%2Celectronics%2C248&sr=1-1&ufe=app_do%3Aamzn1.fos.2b70bf2b-6730-4ccf-ab97-eb60747b8daf

And this one: https://www.amazon.com/DMX9707S-6-95-Inch-Capacitive-Wireless-Bluetooth/dp/B084BWS2YZ/ref=sr_1_2?crid=2YZZVT8I6DZL6&keywords=kenwood+9707s&qid=1687586990&s=electronics&sprefix=kenwood+9707s%2Celectronics%2C248&sr=1-2&ufe=app_do%3Aamzn1.fos.2b70bf2b-6730-4ccf-ab97-eb60747b8daf

or these prices from another vendor: https://www.crutchfield.com/g_462350/Apple-CarPlay-Compatible-Receivers.html?tp=72357&pg=2&fa=1#&avf=Y&nvpair=AG_Type|ffCD&nvpair=AG_iPod/iPhone%20Control|FFNavigation_App_Compatible_@iOS@_&nvpair=AG_Audio_and_Video_Inputs|FFAudio@@video_(Rear)&nvpair=AG_Camera_Inputs|FF1_Or_More_Inputs&nvpair=AG_Steering_Wheel_Control_Compatible|FFAdapter_Required

https://www.kenwood.com/usa/car/caraudio/navigation_multimedia/

Best Buy is cheaper than local:
https://www.bestbuy.com/site/searchpage.jsp?_dyncharset=UTF-8&browsedCategory=pcmcat1493672433779&id=pcat17071&iht=n&ks=960&list=y&qp=carstereosscreensize_facet%3DScreen%20Size~6.95%20inches%5Ebrand_facet%3DBrand~Kenwood&sc=Global&st=pcmcat1493672433779_categoryid%24abcat0302012&type=page&usc=All%20Categories