If you're planning on having any custom auto interior work done to whatever you drive, there are three traits you need to be on the lookout for in whatever specialist you choose to do the work for you. Those three traits are:

1) Attention to Detail. Let's face it, getting a custom auto interior isn't one of life's necessities. It's an extra. A perk. Something you've decided to treat yourself to, and if you're going to spend the money, you want to be certain the job gets done right. No detail is too small, right? If the "look" you're going for requires monograms that match exactly with the car's logo, or a precise type of stitching, then you don't want those details to be overlooked or hurried.

2) Thoroughness. Akin to the above, but a category unto itself. If you've opted to pay for a service like this, then the last thing you want is someone taking shortcuts with the project, as this will inevitably reduce the overall quality. I'm talking about stuff like door panel rebuilds. Some specialists will leave bits of the old material in place and simply glue the new stuff over it. The problem, of course, is that the adhesive doesn't stick properly, and it won't be long before you get rattles and noises as stuff starts falling off. Not good, and not what you wanted when you shelled out your hard earned money, so look for a guy who is not going to take shortcuts like that, but who's going to do a good, thorough job for you.

3) Finally, you want someone who offers a wide range of services. There's no point in having to take your car to half a dozen places to get it just the way you want it, and it tends to work against itself anyway ("too many cooks in the kitchen," you might say), so you need to find someone who does it all. At a minimum, if your custom auto interior specialist can't, or isn't willing to do the following:

Basic upholstery repair/replacement
Custom seat cover design
Custom floor mats
Headliner replacement/Visors & Consoles
Trunks & Interiors (absolutely anything inside the vehicle)
Floorboard repair/replacement
Dashboards
Door Panels
Console buildouts
Custom Covers
And
Convertible tops (repair/replacement)

Then you should probably keep looking until you find someone who will do all those things, and more!

There are tons of people for whom a car is simply a means to get from one place to another, and there's nothing wrong with that, but if your car (or truck, or motorcycle, or RV, or whatever you drive) is more than that for you, and if you want to make aftermarket modifications to make it truly shine, then great care needs to be taken when selecting a Custom Auto Interior Specialist to do the work. Otherwise, you risk wasting a lot of time and money, and set yourself up for disappointment.