Is it ok to hold hands when cuddling, or is this seen as crossing some boundary of intimacy?

Another question is do providers wash their hair after each session? I have a fetish for long soft hair and love to run my hands through it. Should I be concerned about messing it up too much?

I also love to hold hands as well as to massage and stroke about every part at some point. I can not remember a lady who seemed uncomfortable with hand-holding or stroking. Hair is a totally different issue. Some will be fine with having their hair stroked. Others will make it clear that their hair is strictly off-limits. Others may send mixed signals depending on lots of factors, such as where you hands have been recently.

I'll agree with the others.  If she's OK with cuddling, then she's probably OK with hand holding. However, some people (not just women) might feel threatened or constrained if you take hold of their hand/s too firmly.  If she's not a cuddler, I'll guess that hands are off limits, too: simply not wanting to held or held down.

Hair is all over the place. Some girls spend a LOT of time and money on their coiffure: cutting, dyeing, perming, curling, styling, HAIR EXTENSIONS ("Ack! Don't touch my extensions! You'll pull them out!"), highlighting, ... Others just shampoo and blow dry.

If you make a wrong move, I'm sure she'll let you know.

I had a civvie GF with long auburn hair (green green eyes and some serious DDs - Oh man!)... anyway, the best foreplay for her (only second to "whipping it out") was to brush her hair for her. You might give that a shot.

Dude, I can only speak for myself.  I am there to make you feel very good.  Of course you can kiss, hold hands and Whatever else you want as long as you are a gentleman.  I wash my hair and body after each session.  It is okay to mess it up.  If you grab my hair and pull it like a caveman, that is even better.