I have started to look at opportunities.
I came across something that seemed rather interesting. Even more so since I know of the company. I applied. I will add that the role is a bit 'junior' for me, but from what I understand of the company, the work involved can be really interesting.
I got a response. I was asked to give salary details.
How can I convince that salary is not an issue? And that I am more interested in understanding the role?
Let's re-wind a little.
The first response to your application is to ask for salary details, with no prior contact. This should give some indication about priorities for the hire, and even the culture of the organisation. This certainly spells out that, for this role at least, getting someone within a rigid budget is essential (or that previously they have set this too low and spent time on applicants who are too expensive, and haven't adjusted for the market since).
The role is 'a bit junior' for you, but the company is interesting. So you make the classic mistake of the experienced hire - making an application before connecting with someone appropriate in the target business. You would be better now to circumvent this question by contacting a suitable senior person in that business, explain your interest in the organisation (not the role which is a bit too junior). Chances are they would bring you in at a more appropriate level in the same manner of work. And now with someone sponsoring you too.
If you want to look at advertised recruitment, see that as being symptomatic of what is happening in the organisation you are interested in (any organisation). Much of the hiring wont reach adverts anyway. Better to send a message, ask for a coffee or a call. Play your experienced hire card.