Croatia looking into taking over Germany's F-4 as an interim solution

Apparently a team consisting of Croatian MOD and CroAF personnel has visited Germany’s Richthofen air base in search of familiarizing themselves with the F-4 and everything that goes with it.
As Croatian defense minister said, a joint German-Croatian team of experts will be formed to look closely at the idea of Croatia taking over some 20ish F-4s to replace MiG-21 that are getting past their usage date.

How viable is this? Can a small AF like CroAF support a machine like F-4? Also, it is becoming clear that F-4s would be eventually replaced by Eurofighters(again from Germany), an even more expensive jet to maintain.
More importantly, how much life is left in those F-4s? How long can they fly?