Are you meaning the initial advisor, which is now mandatory but was previously advisory, or your Accompagnateur?
I went with an advisor although it was only advisory then, and it wasn’t so much picking one, but it was the organisation in the department Co-funded by ANAH and the department who ran the service. They had a monthly drop in at a nearby mairie. You want along with your documents and information and they sent you back a plan as to what would be best based on what you told them, without a visit so the more pictures and information you supply the better.
The Accompagnateur was, to be honest, partly who would actually reply and consider me. You can, I think, use large or national firms who are accredited, but I wanted someone local who understood the area, the type of house, and could be at my house (or me at his house if he doesn’t do his job properly!) within half an hour. So it became about which local firms were accepting new people and then going from there. In the end I picked a good one and it’s worked out well.
It’s worth saying they have significantly slashed the max amount available from 70k or more to 40k (for 3 class improvements, 30k for 2), which made it less economically advantageous to me, but I decided that some money from the government was better than no money from the government and decided to continue on. After 14 long months ANAH have finally processed the file and agreed, and of course in 14 months devis are no longer valid and materials costs have increased so I’m having to pay thousands more because the government is inefficient, they won’t contribute to that increased expense that was their fault of course. This is not to say it will take so long for you, it varies from department to department, but it is possible.
There is someone on here who is midway through the actual work I think, maybe even finished now, who may chime in with experiences of reimbursement and such.
It’s worth mentioning that I’m within 500m of a historic monument, so I just started the every initial conversation with that, meaning people just defaulted to wood not PVC, muted colours, lime mortar not crépi etc etc and gave sensible suggestions in keeping with the house.