Great fun from Goliath.
A steady solve, filled with witty clueing and brilliant surfaces. Thanks to the setter.

BILL (damage) + (AS (since) acquiring BONG (cannabis delivery kit))
GERM[anium] (first part of, from 16 down’s solution)
CHARLES (His Majesty) + TO + N[ab] (the first)
SOBS* (*uncontrollably)
SAIL (cruise) in (A BUS LANE)* (*out of order)
Double definition
[sto]P AT NO[thing]< (some, <to turn)
Double definition
RU[le] (half of) + [b]RITA[n]NIA (ignoring B[ritai]N (borders))
NATIVES (locals) pursuing ALTER (change)
SHE’D (the girl would)
MUSICAL* (*composition) has RUM (spirit)
“SIGHT” (a sense, “so to speak”)
(L[ive] (beginning to) + LIFE) in UMBER (colour)
Cryptic definition
From the phrase ‘the buck stops here’. From 10 down, the ‘boss’ accepts ultimate responsibility, i.e. that’s where the buck stops. ‘Bucks’ is slang for dollars, from back when buckskins were used as currency apparently.
LO (look) and AD (notice)
(LANDLADY RUNS)* (*amok)
O (love) + AS IS (unchanged)
GO (leave) + (A DOCTOR)* (*cooking)
(EXIT BAR NOT)* (*surprising) – semi &lit
PLASTER MAN (building worker, Spooner’s)
(WHY NO LET)* (*off) during FALL (autumn)
CASSOULETS* (*can be)
DEPART (go) + MEN (guys) + T[rumpet] (intro of)
[ele]M[ent] (its core) in GERANIUM (flower)
IN[j]URE (hurt, after J (Juliet) has gone)
‘Juliet’ is from the NATO alphabet
PRO (supporting) + [Shef]F[ield] (centre of)
[g]E[t] [e]M[broiled] [w]I[th] [t]R[affickers] (second to)
Good fun. My lexicon expanders today were SIMULACRUM & UMBELLIFER.
I agree entirely with Oriel’s introduction – fun from beginning to end.
Splendid anagrams in UNASSAILABLE, LOST CAUSES and, especially, EXORBITANT and I also enjoyed RURITANIA, SIMULACRUM, GOOD ACTOR and FLY ON THE WALL.
‘Australian backwaters’ at the beginning immediately suggested BILLABONGS but it was my last entry, after getting all the crossers. Damage = bill didn’t occur to me (although I’m quite familiar with it and often use it) and I just didn’t know BONG, so I would never have got there from the wordplay.
Goliath is one of the few setters who consistently produce meaningful Spoonerisms, so MASTER PLAN was very satisfying.
Many thanks to Goliath and Oriel.