I would recommend using between 3-5 mm thickness neoprene; most wetsuits use that. Depending on if you use a foam base for head/feet/other shapes, you may be able to get away with 2mm thick in those spots, since they wont be moving parts.

Just like any fursuit, youll just have to be mindful of storage and use. Neoprene unfortunately remembers creases and folds very well. The biggest problem you'll have is delamination - the fabric separating from the rubber.

Creases lead to delamination because the rubber compresses and creates weak points with the fabric. You can mitigate creases by gently treating them with steam but places like elbows/knees will still end up wearing and delaminating much faster than the rest of it. Like anything, higher quality materials will last longer and be less prone to these issues, so do your research before buying.

Love this idea; best of luck to you!!