Assuming the home test counts for your driving licence
Licence vision certificates must come from centres accredited by the licensing authority, which file results electronically — a standard home visit is not that. People pay AED 150–400 at home, then discover they still need the approved-centre test. Use the home visit as preparation, and ask about accreditation before booking if the licence is your whole reason.
Waiting for a child to complain before testing
Children rarely report blurry vision because they assume everyone sees the way they do; the signals are squinting, sitting close to screens, and slipping schoolwork. By the time a child complains, myopia may have progressed for a year or more. An annual test through the school years is cheap insurance against exactly this.
Skipping the licence check because the price was good
An unlicensed test is the most expensive kind: a wrong prescription means headaches and wasted glasses, and an unqualified tester can miss signs that needed a doctor. Verifying a DHA, DoH or MOHAP licence takes two minutes. Booking through a platform that verifies vendors first handles the initial filter, but asking directly costs nothing.