There is no one way to make it to conservatoire and into the music industry.
Both my DH and myself are pro musicians; I came through the more 'standard's route of private lessons, ABRSM exams, JD etc, he came through a route which started as a drummer in a pipe band as a child, drumming in pop bands as a teenager, and eventually Conservatoire to train as a percussionist in his 20s.
We met when we were both playing in the same pro orchestra.
Our DS has just had scholarship offers from all the conservatoires he auditioned for.
Virtually all his musical training has been funded by bursaries and outside financial support. Some conservatoires offer fee wavers for applications.I
There is a huge amount of financial support out there for young musicians - you just need to know where to find it.
Future Talent, Awards for Young Musicians, the Benedetti Foundation, NYO Inspire, the Cherubim Trust - all offer help/ opportunities to young players.
There is no need to have loads of consultation lessons before auditioning for conservatoire. You don't need to be "known" to the colleges.
A lesson to find out if you're the required standard may be helpful, but even then, it won't tell you what the standard of other applicants may be; you could be the right standard but not get an offer because the competition is high in your insttument, for example.
Without doubt, the arts is a tough industry to make a good living from, and it's particularly struggling at the moment. You need to be sure it's your passion, your "calling ", if you like, and know that you'll have a portfolio career which will probably include teaching etc. The conservatoires are very much aware of this these days and are looking to create rounded musicians with lots of different strengths, not just performing - look at any Bmus spec and you'll see optional modules in running workshops, recording skills, promotion, the art of teaching, writing for classical music etc.