Durango is an interesting town. We spent an evening there in June for dinner and touristing, but sadly didn't do the train. The train museum though was quite good...and free as I recall (donation). Lots of stuff, not just trains. Worth planning to do.
I did notice a few MH's in the train parking lot, for train customers only.
we found parking at the bus station a block or two away. It was free parking after business hours, after 5 PM i think, no RV spaces but there was room when we were there right at 5PM on a weekday.
Otherwise, we found Durango to not be RV friendly at all. We had been planning to overnight at the walmart, or similar. Was told no at walmart, and the folks at Home Depot said that just the week prior the city had them sign a statement saying they would no longer allow overnight parking. It was too late to find an RV park so we went on down to Farmington instead to spend our breakfast money there instead.... Sorry Durango, I wanted to enjoy your town longer and spend more money there..... but you made it clear you didn't want it.
Oh, and while circling town trying to find parking and so on we discover a nice trap for big rigs.... 3rd avenue, which is basically a major thoroughfare that borders between the downtown area and the residential area on the East side is marked no trucks. Sadly I was up a creek so to speak. It was one of those roads that T's into 3rd, so no way to go straight, can't turn left or right because of no truck signs.... not enough room to turn around...and can't back up....and and to make matters worse it was on a hill. I guess the folks that dream up these sign placements get a chuckle about not giving truck drivers warning....