I don't think a day goes by without someone asking me what products are best for Crochet Braids. And my answer is always the same....oil based products work best for avoiding tangles and matting. BUT, be careful not to use product too often. Too much product will overcoat the hair and cause it to eventually dry out.
My advice is to use oil based products on the hair 2-3 time each week and re-wet with a water spray bottle on the off days in between. Also, it is very important that the hair is moisturized PRIOR to installation. If your stylist isn't doing this already, you'll know after the first installation because it will immediately become tangled even while its being installed. If you are doing your own Crochet Braids, start with moisturizer, end with moisturizer. You can't go wrong.
Among my favorite go to products to maximize moisture and style retention are Creme of Nature's Argan Oil Leave in Conditioner and Oil Sheen. Both leave the extensions with a light coating of oil residue to keep it from drying out and help it stay soft. If you need to go a little heavier with product because you're wearing a dry or kinky texture, try Pantene Daily Oil Creme Moisturizer or Hawaiian Silky's 14-in-1. These eliminate dry, tangled curls on contact. But be sure to rub the product into your hands and then onto the hair. Pay close attention to the ends where fraying starts first.