We couldn't have been happier when Porsche announced the updated 718 GTS 4.0 twins at the start of the year. With a new 4.0-liter naturally-aspirated flat-six engine replacing the 2.5-liter turbo-four used previously, both the 718 Boxster GTS and the 718 Cayman GTS now produce 394 horsepower, 309 lb-ft of torque, and a soundtrack to go with it.

Now, Porsche's online configurator has gone live for both models, so naturally, we wanted to find out just how expensive they can get. Starting with a base Cayman GTS 4.0 at $86,800, we took a deep breath and chose as many optional extras as we could. Being a Porsche, there were many. Bear in mind that while the color scheme we ended up with may not be to your fancy, our goal was to spend as much as possible, not necessarily create the prettiest coupe we could.

Outside, we started with a custom (unnamed) color option that on its own, adds $11,430 to the base price. Ours defaulted to a distinctive green hue. With that single option, we nearly eclipsed the price of the Cayman GT4. Staying with the exterior, we added 20-inch 911 Turbo wheels and extras like a high gloss black rear wing for $410 and the Porsche Dynamic Light System Plus for $1,180.

Moving inside, a natural leather interior in Espresso added $3,680 and 18-way adaptive seats another $3,030. Only one package, the Premium Package at $3,600, is available, which adds a Bose sound system, lane change assist, and more.

On the performance front, we upgraded to the seven-speed PDK gearbox ($3,730) and also added ceramic composite brakes for $7,410. Because Porsche charges extra for many driver aids, we had to add the likes of adaptive cruise control for $1,670.

Some options were truly ridiculous, such as $1,040 to clad the owner's manual wallet in carbon fiber. It's also worth noting that we couldn't add absolutely every option because not all options are compatible with each other. Despite this, our fully-loaded Cayman GTS came to a stunning $186,878. This includes additional equipment to the value of $67,865, what Porsche calls Tequipment accessories which added another $30,863, and a delivery fee of $1,350. The total isn't far off a Porsche 911 Turbo, which begins at just over $200,000.

While we doubt that anyone would spec a 718 Cayman or Boxster GTS to this extent, the scope of customization is truly mind-boggling. With the more powerful Cayman GT4 hovering at around $100k, our advice would be to add no more than $10k worth of options to the GTS. Any more than this, and you may as well go for the full-fat GT4.