Needed - A GPS that can calculate trips between Post Office Addresses

Well, I sent my Garmin 51 back to Amazon today. I purchased the GPS because my 4-year-old Garmin Nuvi 1450 died. I thought that I would be buying something much better. What I got was something much worse.
Here's the problem: My Nuvi 1450 and the two Garmins before that could create a trip between two or more Post Office addresses. That sounds pretty simple. Google Maps can do it. So can Mapquest, AAA Maps can do it too. The Garmin 51 can't do it. The Garmin 51 can only calculate trips between entries in the Garmin Maps. If you want to create a trip between the Hospital, the Theatre, your favorite Restaurant, and a Museum, the Garmin 51 will do it, but if you want it to calculate a trip between your house and 35 Main St; Albany NY, the Garmin 51 can't do it. If my analysis is incorrect, please let me know.

UPS, Amazon, Home Depot, etc. must have GPSs that can calculate trips between Post Office addresses. If you know of any products that can still calculate directions like my Nuvi used to do, I'd appreciate the information. The Nuvi 1450 has been out of production for a long time, but you can still find a few remanufactured units on the Internet that are selling for prices higher than new Garmins. The buyers must know something.