Newbie - FAQ
You can find it on the main newbie page at the top right under the life preserver.
2) Read back as many pages on this newbie board as you can.
3) Use the search feature at the top of the page to seek out specific subjects.
4) Get VIP membership here and start reading reviews.
Those four things should help you in being less confused. 
If you do all of that and you are still confused, feel free to come back and ask questions on the newbie board.
A general answer to your question, is that most of the good, well reviewed GFE providers will allow MSOG (multiple shots on goal) but it is not a given. This is where you have to read the revews. And the only way to read the important parts of the reveiws is with VIP membership.
Good Luck.
p.s. Your handle makes you sound like a provider.
I was probably the only person not getting laid. That's why I was able to answer those. lol.
Actually a lot has to do with timing. I am often on at 10 or 11 pm Hawaii time. That's 4 am east coast time and 1 am west coast time, so everyone else is sleeping, and I see unanswered questions that popped up late in the evening.