Hewitt, George B.. Abkhaz: A comprehensive self-tutor. 2010. hh:g:Hewitt:Abkhaz:2010
/ʔ/ is an allophonic variant of /qʼ/ in intervocalic position, but can't be replaced with /qʼ/ in [ʔɑj] 'no'.
/fʼ/ appears in the single word /ɑˈfʼɑ/ 'thin' for some speakers; other speakers replace this with /pʼ/.
Hewitt writes the vowels as /ɑɑ ɑ ə/, but here we transcribe them more narrowly as /aː ɜ ɨ/. /aː/ is from *ʕɜ *ɜʕ; these sequences are preserved in T'ap'anta Abaza.
Stress is unpredictable. Hewitt says that "whichever script is finally agreed should serve the Abkhaz-speaking world [out of the options of Cyrillic, Georgian, and Hewitt's own Turkish-based Roman proposal], word-stress should certainly be indicated".