Zec and Xmr are not "lowcost" coins (if we talk about the price of the coin).
Try with Verge. It has a lot of potential, with big community.
Low price doesn´t mean low market cup. Verge just like dogecoin , digibyte, etc have already a big market cap for their huge supply.
If you want a coind that has potential to grow, check Sumo.
Zencash also has potential, but it mooned recently, so i don´t expect it to grow very fast from now on.