That way LE controls the environment and doesn't worry about some guy in the back coming out with a weapon.

On the other hand, there have been some noted LE stings involving incalls.  

The biggest cause of these are complaints from the hotel or neighbors about too much traffic or noise, so remember to be very discreet.

The main way of doing this is to get your clients to flip after LE accosts them as they are leaving your incall; then LE will wait for you to come out for some reason and grab you using their testimony against you.

(still not a lawyer)

One must always be discrete.  You should change location or at least rooms often.  Providing frequently from a fixed location is high risk, since neighbors will eventually figure it out...  LE has to investigate complaints.  A recent bust, the agency had multiple girls working the same hotel room for several days in a row...  eventually, management called LE.  Duhh!  
Direct your clients how to enter & leave.  Is there another entrance?  (One Fav lady, books a room near a rear exit & opens the door for me.)  In other cases, I enter through the main entrance but use a stair &/or side exit...  no one knows when I left.
I hope this helps,
skb

Laws against prostitution are state statues so each state has it's own laws regarding prostitution.  Every jurisdiction within each state deals with the issue differently.  However, prostitution is a misdemeanor in every state which means the police have to witness the violation to make an arrest absent a warrant.

In California it is almost impossible for the police to make an arrest for prostitution without a warrant unless one of the participants is a police officer.  The law specifically states that at least one of the participants has to have the understanding that he or she is engaging in prostitution in order for an arrest to be made.  The legislative intent when including this provision in the law was to ensure people were not mistakenly or intentionally arrested who were not violating the law.  If the police wanted to destroy someones career all they had to do was have a decoy approach the subject on the street and hand her some money.  The police could then arrest her stating they witnessed an act of prostitution.  Getting a conviction might be difficult but the damage was already done.  There was such an opportunity for corruption that the legislature decided include the safeguard in the law.  

Somewhere along the line someone told a story about being stopped by LE after leaving a visit with a provider.  The police questioned the individual about what he was doing and then the police arrested the provider.  This story resurfaces on a regular basis in one form or another.

The only way LE could arrest a provider under those circumstances would be to have the "witness" sign a sworn affidavit attesting to what happened between him and the provider.  Of course he would be testifying under oath that he committed a crime and I am sure most people are not that stupid.  The police would have to prepare a warrant including a sworn affidavit by one of the officers and the witness' affidavit and appear before a judge.  Based on my experience most judges would be reluctant to sign such a warrant because there would be too many loose issues involving a misdemeanor.  However, if the judge did sign the warrant, the police would have to return to the provider's location and arrest her for the warrant.  If she was using a motel and left before the police returned several hours later with the warrant then they would be out of luck unless they knew her true name and where she lived.  If they were somehow able to arrest her and she decided to plead not guilty and requested a jury trial the state's case would depend entirely on the witness showing up and testifying in court against the provider. Needless to say this might make a great story for a TV show but it would almost never happen in real life.  

Concentrating on street walkers was the most common method of enforcement.  It kept the streets clean and everyone was happy.  However, with the advent of the Internet, street walkers have all but disappeared in most places.

Currently, the most common method of "controlling" prostitution is conducting stings.  The police conduct stings because they could not justify not making any prostitution arrests just because street walkers have gone underground.  They would have to convince the powers to be that prostitution no longer exists and noone is that naive.  

Stings are actually more efficient and cost effective than going after street walkers.  The police rent two adjoining rooms at a motel; place an ad on Craig's List or some other similar medium and wait for the folks to arrive.  According to the local newspaper, police in Oxnard, Calif. arrested 30 men in one sting operation in one day.

Another form of enforcement is handling citizen complaints regarding prostitutes working out of a residence.  

The chances of LE going after a single independent provider are very remote but remember anything is possible.

If you work in Ventura County, CA then the whole dynamic changes due to the district attorney's zero tolerance policy.  If that is your case I would be more than happy to provide you with information specific to the enforcement policies in that jurisdiction.

Assumptions and Definitions.

Incall:  The provider has a room/apartment/house where clients visit.  While it is unlikely for the PROVIDER to be arrested using an Incall due to the need for LE to rack up quantity arrests, this is the perfect sting for LE to use to bust clients.  

They set up the 'Incall' and put an ad on CL or wherever and book appointments every 10 minutes so as the string of clients arrives, they are taken into custody as soon as they are induced into making a proposition. Watch out for the ads that are 'too good to be true!' as they ARE!

As always, using well reviewed providers and common sense is mandatory.  

MVR

It's less likely, but not impossible. Please be careful and don't discuss funds or services once the guy gets there.