Times, 4661.

[red46]

18d, 7lets, M?????t, Maiden on river upset sailor's rodent.
19d, 7lets, B???s?a, Starbucks employee in Zanzibar is Taiwanese.
20a, 10lets, D???e?????, Drug dealer hides small notes in log.
21d, 5lets, ????f, Scottish Isle contracted workers.
25a, 7lets, L???n??, Left someone making bread for a student.

[Captain2]

19 Barista - hidden in clue

[frugalfred]

18 muskrat

[Captain2]

21 staff(a)

[frugalfred]

21d Staff(a)

[Lie-in King]

18d Muskrat - 'm(aiden)' + 'Usk' (river) + 'tar' (sailor, upset)
19d "...zanzi BAR IS TA iwanese"
20a Dispensary - 's(mall) pens' (notes) (in) 'diary' (log)
21d Staff(a)
25a L-earner

[Captain2]

25 L-earner

[frugalfred]

25 learner

[scorpiojo]

Muskrat
Bar is Ta
Di s pens art
Staff(a)
L earner

[red46]

Thank you everyone for help, very grateful.