Keep it in for 10 to 14 weeks. I use midrange? hair, about $100 per bundle. When I had natural hair I washed, conditioned, and blow dried my hair prior to install, and added absolutely no oils to it before it was braided. After I would wash and condition the weave and my hair ever 1.5 to 2 weeks. If at home I would air dry for half the day, then blow dry and flat iron the weave hair. I would only add a tad of polisher if it was poufy.
I've never had any problems with matting at all or tangling, and shed hair after takedown was tons but that is to be expected if u didn't actually comb through ur hair for three months. No loss in density, good retention.
I think those with issues matting are using TOO many products that can't be easily washed out or is washing and manipulating too often, possibly agitating the strands around each other ( still unsure because the ends are braided). When I take down my hair feels oily from just the natural oils I produce, and probably left overs from the few products I use sparingly.
Good luck, show us the pics after the install.