I use email as the best way to contact me. I think its a lot easier and more discrete. Many ladies use a cellphone number.  

first email... once gentleman has been screened and verified I can send a text message if needed.  
I rather not, since you never know who has his cell phone.  
Also, my number doesn't allow phone calls

+1 for me too

Allows me to provide the screening info you need, without being overly intrusive on your time.  Phone calls and texts should follow later, at both of our discretion.

As a hobbyist, my preference is txt or call. I'm not a fan of email.

I rather talk to a potential client on the phone so I can try to pick up on their personality, if they sound nice or needy.  
Also I don't check my email as frequently as I should.

email, until the last contact