general help


hi. i am new here so first of all hi. my sisters boyfriend has a 2001 hijet 1300 16v. he is having a little bit of trouble with it. he doesnt have any idea on how to do anything to it. so therefore the burdon now lies with me. (trainee mechanic) anyway. i have never even seen the engine on a hijet so i kno nothing about it other than its under the seat. i need a list of info please people. im planning on doing a full service for him so what will i neeD? how many cylinders is it? what spark plugs does it neeD? im doing an oil change so need oil type and filter number please. also his horn only works when he turns right:S so im assuming this is wiring. his reverse light only works when it feels like and his rear window heater doesnt work at all. what else would i need please folks?
sorry about the long post.
thanks in advance

come on!

come on guys this is terrible. i need help.