Section 262. Performance of the work

After a district shall have been
  established, the administrative head or body shall cause to be  prepared
  by  the  county  engineer,  or  other  county  officer having equivalent
  qualifications, or a duly licensed engineer employed for  that  purpose,
  detailed  plans  and  specifications  for  the  improvement,  a  careful
  estimate of  the  expense,  and,  with  the  assistance  of  the  county
  attorney,  or an attorney employed for that purpose, a proposed contract
  or contracts for the execution of the work.  The administrative head  or
  body  shall  examine  such detailed plans, specifications, estimates and
  contracts and may adopt, modify, amend or reject the same. Upon adoption
  of the plans,  specifications,  estimates  and  proposed  contract,  the
  administrative  head or body shall cause contracts to be let in the same
  manner provided for other county construction projects.  Nothing  herein
  shall  prevent  the  purchase  or  condemnation  of  any existing county
  system, or portion or portions thereof, whether inside or outside of the
  county, necessary for the purposes of  the  county  district,  provided,
  however,  that  there  shall  be  no power to condemn property the legal
  title  to  which  is  vested  in  a  public  corporation  or  a  special
  improvement  district  unless  the owner shall consent thereto. The cost
  thereof, together with the cost  of  construction  of  those  facilities
  proposed  to  be  constructed,  shall not exceed the maximum cost of the
  project as advertised in the notice of  hearing  published  pursuant  to
  section  two  hundred  fifty-four  of  this article. In the event that a
  system owned by a municipal corporation or district  is  purchased,  the
  county  may  by  agreement with the seller, assume the payment of annual
  installments of principal of, and interest on, obligations issued by the
  selling municipality to finance the cost of the facilities so  sold.  If
  payment  of  annual  installments  of  debt  service  is not assumed, as
  aforesaid, the selling municipality shall set aside in a  reserve  fund,
  so  much  of  the  purchase  price received as is sufficient to meet all
  future installments  of  principal  of,  and  interest  on,  outstanding
  obligations  issued  by  it  to finance the cost of the facilities sold.
  Moneys in such a reserve fund may be invested  as  provided  in  section
  eleven of the general municipal law.