Some of the main "rules of thumb" when talking about car covers are really nothing more than common sense. As a sports car owner myself, this is something that has been talked about to death on our forums as well. Here's what I tell people based on my perspective of protecting the paint and purchasing the exact cover that fits your needs.
1. All car covers are NOT the same.
Duh, you say! You get what you pay for,
but the price of the cover IS NOT what should totally influence your decision. Do the research. There is cutting edge technology out today that makes some covers much better than others. With that said, the best cover in the world may not be the best cover for you. You don't want to pay for technology that you will not be using. Ask yourself the following, "Is it for indoor storage only, occasional outdoor use, everyday use, long term storage?" Don't pay for an indoor cover with dust repellent technology
and UV protection if your garage has no windows. UV damage is not a concern for you. Pay only for what you need. You can get car covers today as customized as the car you just bought.
2. Buy the cover that fits your needs.
A superb indoor cover is made exactly for that use. A superb outdoor cover is made exactly for that use. Don't take a cover made for the garage and use it outdoors. Don't take a cover that is made for outdoors and sunshine only, and use it in the rain or snow. Covers are now customized for the climates that people live in and thus, an excellent outdoor cover for someone in Boston, MA may not be suitable as an outdoor cover for someone living in Tuscon, AZ. A cover for a car near the ocean may not be ideal for someone in Fargo, ND. Buy the correct cover for not only the indoor/outdoor use it will see, but the climate that you will be exposing it to.
Also, understand the wording that describes your car cover's purpose.
Water repellent is NOT the same thing as water proof. A cheap car cover will be water proof. It will not allow water to get to your car, but it will also trap moisture under the cover. As you all know, this can cause stuff to rust and create mold and mildew, which will drastically kill the value of your car and make it a hell hole to drive for those of you with allergies (like me). A water repellent cover will keep water off the car, but still allow the cover to breath. These covers understandably cost more, but you get what you pay for in this instance.
Another thing that people never talk about is drying time. If you are on the road and it has rained, you want to have a cover that dries as quick as possible so that you are not sticking a wet cover into the trunk of your car. Again, the last thing you want to deal with is mold and mildew. Various covers have different drying times and this can be a very important consideration if you are on the road.
3. Care for your cover - it's a science.
I bought a gorgeous blanket for my king sized bed once that cost almost $200. I didn't find out until weeks later that it could only be dry cleaned instead of washed. Had I known that, I might not have bought it. You can imagine what it cost to dry clean a king sized, embroidered blanket.
This is something that you need to consider when purchasing your cover. The cleaning instructions are very explicit and not following them can lead to the failure of your car cover, as well as you having your cover's warranty voided. If you are not going to be able to care for your cover correctly, maybe that's not the cover for you. Better yet, ensure that you can care for the cover you choose to purchase.
4. Warranties - they vary from cover to cover and manufacturers.
You will quickly find out that a quality cover will have a much better warranty than a cheap one. There is a reason you are spending that kind of money. Let your fingers do the walking and call the manufacturer. Have them not only explain what is covered with their warranty, have them also point you to the location on the web where this information is posted because hey, anyone can say anything but writing hold up in court. If it is not posted, have them email you a copy of their warranty. Steer clear of anyone who can't or is not willing to do so.
5. Treat your cover as you do your paint.
I use my California Duster to wipe my cover down BEFORE I remove it. After all, all that dust that would have been sitting on your car is now sitting on your cover. My cover allows for that and you should check with your cover's manufacturer to see if you can do the same. You do not want to constantly fold that dirt up in the cover because that side of the cover could come in contact with the car's paint. At that point, it's a big ol' sheet of super light sandpaper. Not a good scenario. It also keeps the cover clean as enough dirt can cause a cover to fail. This is especially true with covers that "breath".
You don't stack stuff on top of your car's paint so don't make this a practice with your car cover either. Just because your car is covered doesn't mean you can now loose your mind and start treating it like it is wearing body armor.
When to use a cover - the most important information you need to know.
Here is the perfect scenario for using a car cover. You have just washed the car and it is spotless. At that point, cover it. If you drive the car, it is no longer clean, period. If you leave it sitting outside for a few hours, it is no longer clean. If you leave it in the garage overnight, it is not clean unless you have some kind of dust filtration system in your garage. Other than someone like Jay Leno, I can't think of anyone who wouls have such a setup. Thus, only after a wash is when you should be covering the car, especially black car owners. The only thing you do by covering a dusty or dirty car is:
a) Dirty up the car cover (the part you DO NOT want dirty).
b) Grind that dirt into the paint.
Not good choices my friends.
So as you can see, your cover will not get a lot of use unless you are anal enough to constantly care for your paint. For me, it's on a car that may sit for a week at a time because it is not my daily driver. Thus, I can uncover a clean car, drive it, wash it again and cover it until the next episode. Add to that I'm a bachelor and have nothing better to do than take care of my car. For you folks with a family life, I feel your pain!
So there you have it, everything you need to consider when choosing a car cover. I will offer this tad bit of info. Car covers made in the USA definitely have their advantage but even those are not equal. As for my personal preference (for what it's worth), I prefer a cover made by the American company Covercraft because they have been making covers since the 60's and their selection is WIDE. I feel that gives them a little more experience in this department. Their two plants that actually make the covers are located in the US. They have a third plant in Mexico but that plant mass produces high volume accessory items and does not make any custom covers.
All custom car covers are made in the two U.S. facilities.
That's the Junkman's take on car covers. Your eyes are probably bleeding from all this reading but at least you are now armed with the knowledge to make a well informed purchase. I have attached a Covercraft purchasing guide to this post that you can use to make a educated choice of your very own cover. Remember, the most expensive cover is not always the best cover for you! Choose the cover that meets your needs.
The Junkman