Yes. We need a covered area to apply the sealant (your garage is fine). We also need to drive your car out into the sun after the sealant has been applied. During the final stage of headlight restoration we apply a resin that reacts to UV light. The UV light cures the resin. We need to apply the resin away from the sun, then cure the resin in the sun! We recommended you expose the headlights to UV for the rest of the day after we have applied the resin, just to be sure it cures properly.