I have had my 2003 disco for 6 years now. when I first got it I had it waxoiled by someone else. Last year I did it again myself.
The advantage of doing it yourself is it will be done better I guess.
It will also be a lot cheaper.
The disadvantage is the "doing" part
I spent the whole august bank holiday doing it.
Day 1 laying in the water from the pressure washer
Day 2 and 3 with rust treatment then Dinitrol running down my arms
and dripping in my hair.
Now,,, I would do it again and will be doing my Lightweight (Norman) this year.
It is rewarding you could say but probably not FUN.