Welcome to the forum.
To answer your question I will use the following girl as an example:
http://www.sex141.com/en/viewid. ... type=2&keyword=
Under services:
$300 Massage + hand job
$400 Body massage
$500 whole package (which includes BM and sex)
Never heard of 'hm' being used.
If you see a girl's listed services with whole package $300 the girl is probably not worth visiting!
Normal terms being used to here:
HJ = hand job
BJ = blow job
BM = body massage
FS = full service
WG = working girl
Enjoy and hope you'll post some reports