(iv) where such person is a local or state government entity, a
refusal to remove architectural barriers, and communication barriers
that are structural in nature, in existing facilities, and
transportation barriers in existing vehicles and rail passenger cars
used by an establishment for transporting individuals (not including
barriers that can only be removed through the retrofitting of vehicles
or rail passenger cars by the installation of a hydraulic or other
lift), where such removal does not constitute an undue burden; except as
set forth in paragraph (e) of this subdivision; nothing in this section
would require a public entity to: necessarily make each of its existing
facilities accessible to and usable by individuals with disabilities;
take any action that would threaten or destroy the historical
significance of an historic property; or to make structural changes in
existing facilities where other methods are effective in achieving
compliance with this section; and
(v) where such person can demonstrate that the removal of a barrier
under subparagraph (iii) of this paragraph is not readily achievable, a
failure to make such facilities, privileges, advantages or
accommodations available through alternative methods if such methods are
readily achievable.
(d) For the purposes of this subdivision:
(i) "Readily achievable" means easily accomplishable and able to be
carried out without much difficulty or expense. In determining whether
an action is readily achievable, factors to be considered include:
(A) the nature and cost of the action needed under this subdivision;