When Apple unveiled the Vision Pro virtual reality goggles last year at a technology conference, many in the audience gasped at the price: $3,500. That’s more than quadruple the cost of a new iPhone and 14 times the cost of a competing headset from Meta.

The headset, which Apple has marketed as a computer, movie player and gaming machine, will arrive in stores on Friday. Ahead of its release, the discussion has focused on its price: Many have wondered why people would pay so much to do what they could already do with their computers, TVs and game consoles.

Yet the true cost of owning the Vision Pro is probably even higher. Try $4,600. That’s because the price shoots up with the add-ons and accessories that many people would want to buy, including:

• Apple’s $200 carrying case to protect the Vision Pro on the go.

• A pair of earphones, such as Apple’s $180 AirPods, to listen to music privately.

• A spare $200 battery pack to get more use from the headset (because with only two hours of battery life, the headset won’t last long enough to play a feature-length movie).

• $100 prescription lens inserts for those who use glasses.

• A spare $200 cushion to make the goggles fit another member of the family.

• An additional $200 for the larger data storage option (512 gigabytes instead of the 256 gigs on the base model) to hold more videos and apps on the device.

And those are just the extras that many consider must-haves. Other options, including Apple’s $500 extended warranty coverage, a $70 video game controller and a very uncool $50 battery holder to clip onto your pants, could drive the price well above $5,000 — before tax.

While I have your attention with these breathtaking numbers, we can all learn a valuable lesson from the Vision Pro about “phantom costs,” the add-ons that significantly inflate the amount we spend. For electronics, including smartphones, computers and virtual reality headsets, they can include cases and charging gadgets.

A clear grasp of the true cost of tech ownership is crucial for any consumers trying to stay in control of their budget, said Ramit Sethi, a personal finance adviser. He said he had learned about phantom costs when he bought a Honda Accord about 20 years ago. He initially thought he was spending $350 a month on the car, to pay off his loan. The true cost ended up $1,000 a month after he added up maintenance, insurance, gas, parking and tolls.

“Companies count on you not being able to run the math,” said Mr. Sethi, who hosts a podcast on money psychology. “The bigger the purchase, the more money you invisibly spend.”