The built-in DVD-based sat-nav on my old Toyota Avensis stopped pairing with phones some time ago. I dismantled the dash, took the enormous black box under the front seat out and with a single simple patch-cable (no wires cut, no soldering, no sticky tape) i removed the head-unit and installed a Sony Apple Play head-unit. Pairing this with my iPhone I use WAZE (free for Android or iOS) and find it better then either Google or Apple maps. My car speedo indicates speeds slightly higher than actual road-speed, WAZE indicated speeds are accurate and shows red if I exceed road-sign speed limits, and she also informs me of impending speed-checks (random ones) and road & weather conditions. Point-to-point times are good and the ability to plan routes in advance on the phone is a god-send.
Any downsides? Spending €320 for this kind of stuff for an old car might seem like madness, but i now have sat-nav, decent sound (the new system drives the speakers better) true hands-free and accuracy. Yer wan is a bit of a pain voice-wise when she interrupts The Beatles, The Stones or FleetwoodMac, but I might try getting Moira from my phone working in WAZE.
Nothing to sell here, WAZE is free on the App Store or Google; give it a whirl.
p.s. Sony XAV-AX1000 Media Receiver (6.2 Inch, with Bluetooth and Apple CarPlay) and Connects2 CTSTY001.2 + CTMULTILEAD.2 Steering Wheel Retention Compatible for TOYOTA Avensis all you'll need if you want to convert your old Avensis, that and a couple of screw-drivers and some patience routing wires.