Let's try to imagine how this will actually play out. You're web surfing & see her Backpage ad.  She's amazingly hot in that black bikini--just like that cheerleader from high school that you always dreamed of fucking.  You text her, & she's free right now if you hurry!  You jump in your car & gun it across town, running yellow lights till you get to her hotel.  She texts you the room number.  You knock on the door, your dick throbbing against your leg.  An unshaven cop opens the door & flashes his badge.  "Step inside, handsome. You're under arrest".  

  Your soul leaves your body.  The cop pushes you up against the hotel wall and pats you down, confiscating everything in your possession, including your precious cell with that magic number.  The cop reads your miranda rights and you're hoping this is all a bad dream & you'll soon wake up next to your sweet wife.  You don't.  

 You:  I need my cell, I want to call my attorney!  

 Cop:  Really?  I want a burger & fries. You can chat with your lawyer later.  Right now, we're going for a ride downtown.

 He cuffs your hands behind your back and takes you to an unmarked car.  He drives you to the ugly part of town, where you never go.  He leads you into a drab gray detention center for booking.  There are scary tattooed men looking at you.  One of them sniffs your neck and says "you smell like a little bitch".  You really need to pee.  They take you to a brightly lit room, and you're squinting like a frightened rabbit.  They snap your mug shot.  It will be posted on the internet in the next few hours.    

  Time crawls, plenty of time to think about this nasty turn your life has taken.  What are you going to tell your wife and kids, oh no.  You're eventually taken to a processing station.  There's a "bail schedule" posted for non-violent offenses like 'solicitation' where you can pay your bail and then be released.  They turn over your possessions, including your precious cell.  You can call your attorney now.  --z

h reply to the OP was an attempt to underline the following:  If you get busted, the real damage is *usually* the arrest and the exposure.   Your attorney cannot prevent either.  It doesn't matter if you retain the best attorney in town.  I'd bet an ethical attorney would refuse the OP's silly retainment offer.  He'd probably give the OP the following legal advice:  "Don't do it."

  But we're going to do it anyway.  If you get arrested, you definitely will need an attorney.  If it's a first offense, a competent attorney  will usually resolve your case with little or no jail-time.  My concern with the OP is that he seems to have a child-like sense of security in "pre-selecting" an attorney.  By the time your attorney shows up, the real damage has already been done.  An arrest is a matter of public record.  If your job requires any kind of security clearance, you may lose that clearance.  Any google search on you will hit that arrest record.  Your mugshot will be on the internet from that point forward.  

 The consequences here are unbelievably harsh, considering it's a victimless crime between two consenting adults.  But that's the game we're playing.  --z

can not legally advise you to break the law.  
There are some good videos, that everyone in this hobby should understand.  Every jurisdiction has different laws, varying in important details about your rights.  If you are "caught" you'll likely be arrested.  Your property likely seized if only to keep it secure.  The police legal right to search varies.  

I've seen a write up describing an arrangement whereby a competant party who cares for your children...  who keeps a sealed  envolupe with emergency instructions...  Possibly a link to another trusted person who could make bail if needed.  

And for gosh sakes...  while exercising your rights to keep silent...  do not resist.  Do not conscent to a search.  Do not have drugs or other illegal items which would add to the charges.  

It would not be a bad idea to have an initial consultation with an attorney...  but don't expect to have one an your beck & call.  Nor might that be right right one if you are busted in another location.  

There's not an easy answer as you seek.