Pertaining to ladders, many RVs seem to be deleting them lately. Yes, in some cases they're an option.
Whether to insist they put a ladder on is a personal choice. One of the reasons, or so I'm told, that many manufacturers are choosing to forego the ladder is that they've determined that a great number of RVers either do not wish to go up on the roof or go up very infrequently. There's no storage space up there so it's not like you're needing to go up on the roof every trip. To perform maintenance up there, whether it be on the a/c, other items up there, or the roof itself for cleaning and inspection, again is not something one has to do every trip.
I do not see a ladder listed as an option for the Alante. Therefore, the dealer would have to do a custom fit ...or farm it out to have one custom done. If it was a factory option or a dealer-installed option, then the price would be relatively reasonable. If having to do an after-market installation, it may or may not cost quite a bit extra.
Most, including myself, would probably just opt to carry a collapsible ladder and store it in one of the storage compartments for use whenever needed to get up on the roof. I have a factory installed ladder that came standard on my rig but if it didn't come with one, I personally wouldn't make it a deal breaker. I do carry a folding step ladder that is almost 6' for other purposes since I do have a permanent ladder in the rear.
Here is one at Amazon that is popular with RVers:
Leapair 12.5ft Telescoping Ladder Aluminum Telescopic Extension Tall Multi Purpose
They're collapsible so take up very little space and are relatively lightweight yet can support someone over 300 lbs. They also come in other sizes and other manufacturers make them. Plus, you can also use them away from the RV if needed so it's not like a ladder that is permanently installed on the RV itself.
The Alante looks very nice, btw. It's nice looking and appears to have a very functional floor plan. *thumbs up*