Bikes are for fun.
If costs is the BIG consideration..not the fun...one makes sort of weird bike decisions
the cheapest bike is used.....the ones that are most unpopular, most undesirable are the cheapest...the best buy if $$ are the main decision point
BMWs are not cheap...either new or used because they are highly desirable. ...ie Fun
to me debating the cost of a valve adjustment on GS or a super Teniere is like trying to dance on the head of a pin