Hi 
If you're not particular, you can bring it to any workshop without
appointment, coz you can always go to next workshop if the 1st
one's real busy.
Having been around for 4 years, most shops worth their salt will
know how to sevice your car. It's workshop bread and butter.
You have to service between every 5000km and 10000km, coz you have
to at least chnage the engine oil and engine oil filter during this
interval if you wanna keep your engine in good condition. You will
have a choice of mineral engine oil, which is cheaper but have to
change every 5000 - 6000km. Or you can choose synthetic engine oil,
more expensive, but you need to change only about every 10000km.
Each time you go for such servcing, just tell the workshop any
problems you have with the car.
If you have the car manual, there should be a table inside that sez
what to inspect / replace at which interval. Else, if you don't
have the manual, you can let us know which car you are drivin and
the bros here will direct you to a forum where you can really get
answers for your specific car and maintenance for it.
As for cost, there's 2 components to everything. Cost of part and
cost of labour.
If you know what you want, say engine oil, you can keep an eye out
for a good lobang on these forums, buy it and bring it down
to
workshop and just pay for the labour.
If you go down to the workshop empty-handed, synthetic oil + oil
filter + labour may cost about
80 - 120, excluding other stuff that may be wrong with your
car.
Hope this helps, and sorry to hear about your dad 
