draining/flushing of radiator water/coolant

[meledson]

newbie here. mga sir, where or what shops can i buy the prestone coolant? what is the best to use the premix or the concentrated one? and last, what is the best shop na gumagawa ng flushing ng radiator? di po kase pwede sa place namin dahil maraming bata and delikado yun. need your reply mga sir. thanks

for me, better ang pre mix para optimal ang timpla.