Let's assume you have a landing page trying to convert a visitor. And you have a chat/support software that allows you to personalize in terms of location and OS. You're trying to be some sort of authority in a certain niche. What would be the best way to approach visitors and get them to chat back?
We tried some basic approaches like "Hello, please let us know if you need help with this and that as US guy" or similar. Not working out.
I'm aware of the fact that it all depends and you have to test, test, test. But I'm a bit stuck right now and would need ideas what to test. So any suggestions are appreciated 
I am prety sure that there are chat service that have bots for that. Just open some adult dating offers with exit pops and look for chat screens loaded on exit. Just contact chat sevice company and ask for price or 'learn' from their bots.
I would use a "customizable" live chat script (coded in PHP) and conversion rate would improve pretty nicely.
An example - http://i.imgur.com/taRIQ2o.png
(if anyone wants me to share this, let me know)
I know all those adult/dating approaches but this is a reputable service where visitors are seeking for information/help and not a f*** buddy 
What exactly do you mean by customizable? As already mentioned, I have that already and can customize visitor OS and location. Right now, I cannot think of anything else that is customizable.
When I was running my e-commerce shop, I'd always offer to check if there's any discounts available.
i think u can try those hosting and server services? they always seem to have a chat function, and they are not the adult scammy kind. these companies are like justhost, IBM etc