Hi Saige,
Safe healthy sex is of course one of the big issues. The main houses have done a good job in giving us the confidence that the WLs are healthy and regularly screened. (unlike punters who may or may not!)
Many potential clients need this confidence to make a booking.
A way out might be worth considering, I am not sure if this is practical but a meet for coffee (punter pays!) , no obligation policy, or something for new clients to confirm that the marketing and the girl are one and the same, might be good.
Number withheld calls seem a risk for the WL, perhaps for no shows and personal safety, however irregular/impulse punters do not have a spare sim card and greatly fear call backs from WLs. One strategy I have encountered is for the WL to withhold their address until a confirmation call is made from the punter just before the booked time. Not sure how to address this otherwise.
So, an established house offers safe anonymous service with no obligation, (unless an upfront fee is required). A private WL needs compete with that. Even though a private WL may cost less the extra money is often easier to find than taking the perceived risks.
For what's is worth
Cheers