I got a detailed flier from my dealer: about $3k for 2 - 100ah battle born batteries and an upgraded converter on a '21
Caravel 20FB.
Not even close to worth it for our tastes as it's about a 35% upcharge versus about a half hour of diy work and ordering parts direct.
Parts listed:
Battle Born Battery BBGC2H 100ah
Controller:
All '21 and Classic '19+ have a lithium compatible controller, just change a setting for lithium
All '17-'20 + '17-'18 Classics get an updated controller "Sun Explorer II 40 amp kit" (existing display is compatible)
'16 and older needs new controller and display
Converter:
'21 Basecamp 20 is compatible, requires a switch onboard.
All others:
30A WFCO WF-8950L2-MBA
50A WFCO WF-9850L2