嗎 lifts a flat statement into a question and is neutral. Tail 沒(有) builds the A-not-A choice into the end and asks specifically whether it did or did not happen. Use one, never both.
沒(有)1 sits before the verb and negates the event (沒參觀 = did not tour). 沒(有)2 sits at the tail and asks the question (參觀過…沒有?). Same word, before-verb negates, end-of-sentence asks.
A-not-A repeats the verb with 不/沒 in the middle (去不去 / 來了沒). Tail 沒(有) leaves the affirmative whole and parks the negator at the end (參觀過…沒有). Both offer yes-and-no; the negator's seat differs.
✗ 你參觀過校園嗎沒有? → ✓ 你參觀過校園沒有?
✗ 你沒有參觀過校園?(asks nothing — reads as a flat negative) → ✓ 你參觀過校園沒有?
✗ 你參觀校園沒有了? → ✓ 你參觀過校園沒有?
English tags the question with intonation or a separate "...or not?" clause; learners reach for 嗎 and bolt 沒有 on as well, doubling the question device.