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.
Booking separate visits for one household
The call-out cost is baked into every solo booking, so a family that books three separate visits pays the travel premium three times. Almost every vendor discounts additional people in the same visit, typically AED 80–200 each. Bundle the household, especially outside Dubai and Sharjah where travel is a bigger slice of the quote.
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.