It's not unusual for control freaks to prefer submission in the bedroom. Sometimes it's nice to be told what to do.
Do you know about 'Safe Words'? They are basically words you arrange with the other person to let them know that you are (a) uncomfortable or (b) unhappy. These words are never 'No' or 'Stop' but rather 'Amber' 'Red' or 'Banana', or anything incongruous.
Also, I know you feel safe with this man, but it's still not a good idea to let him tie you up in such a way that you can't untie yourself. Sometimes people have fantasies in their heads which aren't achievable in real life, you don't want to take a risk of things ending badly and losing a good client and your trust.
Re: pricing. Ask him about other people. The chances are it will just be the two of you, but if not, add on another 100.
Good luck.