I was wandering, do you use a condom when receiving oral from a prostitute or escort.

BBBJ is one of my two deal-breakers, the other is DFK.  If they aren't on her menu, I won't see her.
Some guys do request CBJ, many are like me, however.  Many providers only do CBJ.  In both situations, it's their choice, but I have my choice too.
Swim

when CIM, COF, or COB is the end result.

As the other posters mentioned, some girls will do CBJ only others will do BBBJ....It would be my thought that the ladies that provide BBBJ would also provide CBJ if requested. You just need to speak up and make that request.  So just depends on what you are wanting. It pays to do your research

Have fun and play safe!

Summer

I prefer bbbj, but I have received a very spirited cbj or two before.  If the provider wants to use a condom, I won't argue.  But, if you do your research before you go, you'll know what to expect.  

If you insist on using a condom, that's your choice, too.