most bikes do have a small adjustment on the shocks that you can lower buy turning the shock position,I dyi that myself on every bike Ive had, my inseam is only 28" lol, it doesnt throw off the balance because its designed to be in any other the 3 positions
if you wish you can also lower the front forks a bit but that can change the way the bike handles, personally i just take it for a ride and find where i like it
but if you need it lower then that or really want someone else to do it i would also suggest transcanada, I have had good service there