Welcome to the forum maireadahayes, ......how long's a piece of string? Everything will go up given a decent time frame.
I don't know much about Fawkner, however Coburg and Glenroy are good areas and both now IMHO fully priced.
I don't know what your budget is, however the Glenroy end of Broadmeadows offers good value for 600-650 sq m blocks with rental houses on them for now and with development potential City of Hume is pro-development. It has good amenity, infrastrucutre and is still close to the city. Also one of the 2030 transit cities that state govt has ermarked for denser development.
If you are after units say in Coburg or Glenroy, then try for 2-3 BR and two bathroom, close (say 300-500 m) from a train and with amenity such as schools, shops, buses, etc.
Obviously they get cheaper the further you move out Broady cheaper than Glenroy, cheaper than Coburg, cheaper than Brunswick, etc. Have a search on the Where to Buy forum for those suburbs and see how you go.
Good luck