The development prospect for customized sun/UV proof waterproof car covers for cars is highly favorable, driven by several key factors including:

1. Growing demand for car protection: As the number of cars on the road continues to increase, there is a growing demand for products that can help protect vehicles from the elements, such as sun and UV damage, rain, snow, and dust.

2. Advancements in materials technology: Advances in materials technology are making it possible to produce car covers that are more effective at protecting vehicles from the elements. For example, the use of waterproof and UV-resistant materials is becoming more widespread, allowing for the creation of covers that offer improved protection.
   

3. Increased focus on sustainability: The increased focus on sustainability is driving demand for environmentally friendly products, such as car covers made from recycled materials.

4. Personalization and customization: There is a growing trend towards personalization and customization in the car cover market, with consumers looking for covers that are tailored to the specific make and model of their vehicles.

5. Rising disposable income: As disposable income levels continue to rise, there is a growing demand for high-quality car protection products, such as customized sun/UV proof waterproof car covers.

In summary, the development prospect for customized sun/UV proof waterproof car covers for cars is highly favorable, driven by factors such as growing demand for car protection, advancements in materials technology, increased focus on sustainability, personalization and customization, and rising disposable income.