Most cost- and time- effective fencing, apart from perhaps hedging (impractical for small gardens), is concrete posts with drop-in panels.
The posts don't blow over or rot and if you lose a panel, you drop a new one in.
As long as you don't do anything stupid, like staining or treating the wood on a yearly basis, your effort & financial outlay is minimal.
I do like shadow box fencing (my Dad installed that in his garden in the 80s) but... wooden posts. A few years later, you're starting from scratch.
All opinions are equal but they are all equally bad (apart from mine, obviously).