In which formats do you deliver the songs?
Once the band is 100% satisfied with my work, I traditionally send the final master in 4 formats:
wav 44,1kHz/24bit online (tailored for online streaming services)
I can also prepare unmastered versions, vinyl versions as well as click-tracks and backing tracks of the songs for rehearsing/concert needs for a small fee.
When I do music production for the band, I usually add separated audio subgroups for every band member (Drums, Bass, Guitar 1, Guitar 2, Keys, Vocals,...) in wav 44.1kHz/16bit.
I can also send the notation of all the instruments for a small fee.