VEVOR Outdoor Stair Railing Kit, 152 cm Handrails 0-5 Steps, Adjustable Angle White Aluminum Stair Hand Rail for The Elderly, Handrails for Outdoor Steps

looking at the 152 cm outdoor handrail kit for $105. I have 4 steps, concrete, while it says that this rail is adjustable, just checking that this is easily adjustable for someone like myself who has not done this kind of work before. How much is the post and packaging and what other cost involve ? Thankyou Angie