[jtrtoo]

1. Don't expect you'll be cost effective for all potential clients that come to you with this sort of situation.

2. Charge a fixed fee - or even hourly - to figure out wtf is going on and assess things. This is effectively a discovery/consult. For some reason many independents can't wrap their heads around charging for what seems - to them - to be "nothing" but it's literally what consulting is. Get into the issue and help the client map a way out. Then...

3. If you want to help the client implement the map, you are also now in an informed position to give them a fixed fee arrangement to do this - the implementation bit. Or if you stick with hourly you can more realistically set expectations and estimate workloads.

Most independents are great at #3 (though most seem far more comfortable charging hourly for this implementation work rather than fixed fee, but that's fine too - at least they'll be able to estimate it better after doing #2 and end up with a better reputation), but horrible at realizing their real value is in #2 (as well as bridging the gap between #2 and #3).

P.S. If you invest in getting better (more comfortable and effective) at charging fixed fee you can rightfully charge more because you are literally being paid by the client to offload uncertainty (risk) onto you.