Wigs Mohair - How much material?

It really depends on your fiber (how fluffy is it? how fine?) and how dense you make your wefts, how long they are, style of the end result, etc! Since this is by weight and not volume, 2oz (or however many grams) of shorter locks is going to go further than 2oz of longer locks (if that makes sense, hopefully it does). So it's going to depend on a lot of factors.

Generally, a 7/8 wig will use up about 1oz/28g of fiber if you're using something fine like mohair or alpaca and not trying to make the wig very long. Better to get more rather than not have enough, generally speaking, but you need less for something that is very thick like teeswater. If the seller is one who sells a lot of fiber for doll hair, you can ask them as well. There's a bit of trial and error here, though.

 

I typically use 14g or 1/2 an oz for MSD's, probably closer to 10g for yosd's when it comes to alpaca. Mohair is much fluffier, and depending on how you use it, or lay it down, you can easily need a full oz due to the lock construction.