How often do you tip, and how much? I've never tipped much, the two regulars I've had over that time never seemed to care and others I've seen provided good service, but I just saw a poster that said he tipped $100! What are your thoughts on this?

For higher priced gals and/or overnights, it gets too expensive.

I don't tip highly paid professionals. I don't tip my lawyer, doctor or my CPA.  My CPA puts in about 3-4 hrs of work on my taxes and charges me about $1000. Why does he need extra $20 from me at that rate? Tipping him would be a good way to lose a very good professional..  A bar tender, on the other hand, makes under minimum wage, and without tips she rather work fast food..

The best tip is repeat service.  

Spot on.

I certainly tip less often than this topic comes up. That said I have tipped 100 or more several times.

Many ladies charge the same (or sometimes less) for outcall than incall so in that case, I think its only fair to give them extra $ for their travel, time and trouble.  
Other times, some ladies just go above and beyond in attitude, attire, time, etc and I always felt those ladies should be compensated for such. I also tend to tip a lady if she is so kind to let me give her name for numerous referrals, sometimes out of the norm.
For example, there were several ladies I hadn't seen in quite awhile due to Covid, and they were very understanding and kind, and relaxed their typical maximum of 6 months for a referral for me.

back in the day, the rate was $300 and I knew she probably only got part of that, so I gave her a tip. Normally I don't, in fact almost never.

in their schedules for guys who don't tip . . . . . .  until they can fill that slot with a guy who does.

Any lady who would cancel a date with a gent because he doesn't tip is not a lady I would ever see.  And I would guess, most gents would feel the same way.  Now if the date has not been made, different story.

all of the things the overpriced Indies of recent years are trying to convince the gullible are not only routine but expected.  

Many of my clients tip sometimes $100 all the way to a $500 tip (this is rare the 500)
Some clients will bring flowers,Amazon or lingerie gift card.
And some clients do not tip at all.
Every gent does what he feels is best for him.
Regardless of the dollar amount I appreciate when I receive a tip but it is never a requirement.

Get better service or treatment or a little extra the next visit.?

Ever had a provider cancel? Might be because of a favored customer.  
Ever have a provider ask to bump the time an hour?

They do it but are not dumb enough to tell you.  I have been a real life boyfriend to a number of providers, and so I have learned how they think.  They will bump you for a customer who tips, but they are not stupid enough to tell you.  Like I said above, they are happy to have a non-tipper's business until they can replace him with a tipper.  They will just come up with an excuse, like they had to call a plumber or some other service person, they just lost a crown and need to go to the dentist, or they're coming down with a cold, etc., all good excuses that COULD be true.  Being ignorant of what really happened eliminates any awkwardness in rebooking at a time she can take a non-tipper.  They will not let you know when you get bumped, because they still want the OPTION to take your business when they don't have a better choice.  Their business is about revenue generation, and tippers generate more revenue.  It's not personal, it's a business decision.

I generally leave a tip somewhere she will find it later with a note. I usually leave $100. I do it for two reasons. One, I had a good enough time to want to see her again. Two, I’m hoping she appreciates it enough to remember me next time I call and (as others have pointed out) maybe give me priority over someone that doesn’t. TBH I don’t expect a 100 tip to go that far in that regard, but it sounds like there are a lot of guys that don’t tip at all, so who knows.

"a little extra" do you mean do you get to go deeper on the next visit?

I tip every time. Its always a gift card from something from their website. $25 or so. Nothing too extravagant

"do you get to go deeper, do you mean you get to be stupid?

are too tightly wound to joke around with.  That's okay.  There are many guys here who are so serious about paying for sex that they suck the fun out of this board and the hobby.   Since you're new (as proven by your question) and too scared to use your real TER username, I'll give you a pass.  Maybe you will lighten up someday.

When you get your ass kicked you are falling back on your old lame worn out excuses of it was a joke, you are joking around. Will you also claim poetic license too.  

are so tightly wound.   I won't out this alias, but it should be pretty clear to everyone who you are.  LOL

.why.. they work for themselves. An agency girl.. yes.

I'm a provider and when I do get a tip, I've noticed it's always $100. Ofcourse it's never expected but always nice when it happens

If she went out of her way or stayed longer. The ladies I see routinely do these things. They get a tip.

I tend to spend time with companions on the higher side for the rate scale. Thus I not in the habit of tipping. I have slipped an extra 100.00 now and then for ladies that I repeat with but thats not typical for me..