EurAide just saved me a bundle on rail fares!

Is this the price you are paying per person or for ? people total? Are you going directly from Trieste to Berlin (19h by train for ~$200pp) or are you making overnight stops along the way in other places?

Our itinerary (2 people traveling together, first class where available) spans a period of about 15 days, with stops in Venice, Vienna, Budapest and Prague and others.

They are definitely saving you some headaches caused by dealing with several country's train systems over multiple days and locations.

FYI: I checked the itinerary for a trip 30 days out for 2 people 1st class using advanced purchase tickets:
Trieste > Venice SL, 40 euro (Regionale Veloce)
Venice SL > Vienna, 168 euro EC direct
Vienna > Budapest, 58 euro Railjet
Budapest > Prague, 38 euro MAV 2nd class
Prague > Berlin, 118 euro EC direct
That comes to 422 euro, about $475 at current exchange rates.

Euraide, I believe, does perform an essential service, primarily booking reservations that one cannot get online. However, they are far from the only way to save money. I don't think they have access to any fares that a reasonably informed traveler can't find on his own. Looks like you could have saved several hundred more dollars vs paying Euraide by asking Sam for free advice.

I am not familiar with the Bahn apps. I use a real computer, so I don't do apps. However, I don't think it gives fares for travel outside Germany¹ (the full site doesn't), so how did bs come up with an $1100 estimate using the Bahn app.

Euraide has a Bahn ticket terminal, and, although you can't book trains outside German online with the Bahn, you can at a Bahn counter, so Euraide could have booked all of it. Euraide books your ticket at the same price you would pay over there, then sends them to this country. They charge a fee of $60 or $110 (the website is somewhat vague) for the service², so if you can figure it out on your own, you're ahead to do it yourself.

¹ You can usually get prices online for a leg or even a series of legs with one end outside of Germany and the other end inside Germany. German Rail does not sell single online tickets for a trip with both ends outside Germany.

² from the Euraide website,
"Our basic fee for suggesting and arranging an itinerary, based on your wishes, is $30, plus an additional $30 for handling and shipping in the United States."

"Customized price quotes may be made for $50. This fee is separate from the consulting/shipping and handling fee."

BTW, Bahn Savings Fare tickets for Prague to Berlin start (92 days out) at 58€ for two people.

EurAide does have very detailed knowledge of the fares, and their service to navigate those for you is worth something. Sure, Lee may have given much of the same advice, and readers can find it on their own in several places, but not without a learning curve, research, and taking time to book everything.

"their service ... is worth something."

But sometimes not that much. Sam found 422€ but, as I pointed out, with more advance purchase it could have been 384€ ($426). I think an extra $274 (over 60%) is a lot to pay for service.

Like I said, Euraide is good for getting reservations that are impossible to get online, but I would not be likely to use them for straight tickets.

Seems like this comparison is incomplete. I don't see that the reader provided you his full list of destinations or travel dates.