Open the door and say, “ahhh.” Your master bath can be more than just functional; it could be a spa.

Bathroom remodeling continues to be one of the most popular home improvement projects. It ranks consistently among the top 10 most reviewed categories on Angie’s List, which has more than 700 home and health categories.

If you’re moving beyond the imagining stage and are ready to get serious about renovating a bathroom, here are trends and tips to keep in mind, compiled by our consumer research team.

What you can do with a bathroom depends on its size and who’s using it.

Hall bathrooms are commonly used by kids and guests, and an update may be focused more on making the most of a high-traffic, cramped room. Ideas include replacing a mirror with a medicine chest faced with a mirror, or replacing a pedestal sink with a vanity that has cabinet space.

A master bathroom, however, is usually larger and more private. It’s a likely candidate for a spa makeover. Some ideas from highly rated remodelers:

• Replace the tub with a luxury shower featuring multiple showerheads and handheld sprayers, or a large rain-style shower head.

• Create a fresh, clean look with a frameless glass shower door.

• Expect some stress.

• Focus less on the latest design trend or fad, and more on elements, fixtures and colors that will stand the test of time.

• Incorporate universal design – which is intended to ensure that a project is useful for people of all ages, abilities and sizes. Among the ideas: Replace lower toilets or sinks with taller options that require less stooping or bending.

Plan to do your homework before starting the project. Be realistic about your budget. The average cost of bath remodeling in 2013 was $18,538, down slightly from 2012, according to the National Kitchen & Bath Association.

Before you start talking to contractors:

• Check websites and magazines for designs and ideas. Research materials and products at showrooms and retail stores. This will help contractors more accurately estimate the time and cost for your project.

• Talk to neighbors, friends and family about their projects. Check contractors’ reviews on a trusted online review site.

• Get multiple bids and ask for and check references. Questions to ask include: Did the contractor meet expectations? Were there delays or miscommunications? How did the contractor handle requested changes?

• Get at least three written estimates that clearly define the project and what materials will be used.

• Make sure you can reach a contractor when you need to.

• Be sure the contractor you hire is appropriately licensed, insured and bonded. Bathroom remodeling work often requires electrical and plumbing work – two of the most often regulated trades.

• For most bathroom remodeling projects, expect to pay handsomely.