You want the shower to be the end of the problem. It is not the end yet. A walk-in shower quote tells you what someone plans to build. It does not tell you who fixes it when a seal fails, who pays for water that gets under the floor, or whether the inspector approved the work. Those answers belong on paper before you sign, not in anyone's memory after the crew leaves.
Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.
Read the scope line by line
Most quotes list the new unit and the install, then leave the rest as included or as needed. Ask for a scope sheet that names every item the job touches. Look for removal of the old tub or pan, disposal of the old material, plumbing changes (supply, drain, and any relocated valve), electrical work for a fan, light, or outlet, subfloor repair if the old floor is soft once it is opened, wall repair and paint, and final caulk and cleanup. If an item is not written in, assume it is not in the number.
Ask how the contractor handles surprises. Old floors and walls often hide rot or damage that only shows up after demolition. A solid quote says how hidden damage is found, who approves the extra work in writing, and how it is priced before anyone starts it. If the answer is vague, you do not have a quote yet. You have a hope.
Check the permit and the license
Ask who pulls the building permit and whether the permit is named in the contract. Plumbing and electrical changes often need one, and unpermitted work can cause trouble later when you sell, refinance, or file an insurance claim. Ask for the contractor's license number and check it yourself with the state or local licensing board. Ask for a current certificate of general liability insurance and proof of workers compensation coverage, and if you can, ask the insurer to send the certificate to you directly. Do not rely only on a copy the contractor printed.
Separate the two warranties
A shower job usually has two warranties. The manufacturer covers the unit. The installer covers the work: the connections, the seals, the drain, the grab bar blocking, and the joints in the tile or liner. The installer warranty matters most when water goes where it should not. Ask for both in writing and compare them. Ask how long the installer warranty runs and whether it starts at the final inspection or on the day of install. Ask what counts as a claim, how fast the contractor must respond after you report a leak, and who comes out. Ask whether the warranty still holds if the business changes its name or closes. If it does not, ask who stands behind the work then. Ask whether the warranty excludes damage to the floor below or the wall behind the shower. Often it does, so find out whether the contract makes the contractor pay for that damage or leaves it to your homeowner insurance. Ask whether using a different plumber for a repair would void the manufacturer's part. Get that answer now, not on the day you need a fix.
Make the leak clause a real clause
Ask the contractor to write down what happens if water leaves the shower area during the warranty period: who you call, how long they have to respond, who pays to open the wall or floor, and who pays for the damage. Confirm that the clause is in the signed contract and not only in a sales brochure. Only the contract counts.
Pay in steps, not all at once
Ask for a payment schedule tied to finished work: a deposit, then materials delivered, then rough plumbing inspected, then completion and final inspection. Do not pay the final amount until the final inspection passes and the punch list is done. A deposit is normal. A large balance due before any of the work is visible is a reason to ask more questions. Keep the signed contract, every change order, and every receipt in one folder.
Test the room with your parent before you choose
A shower can match the quote and still fail the person who uses it. Before you sign, walk the route from the bedroom to the shower the way your parent would really use it, with the walker or in the chair if that is how they move. Check the threshold height, the door swing, the space to sit and turn, the reach to the controls, the handheld spray, the grab bar positions, and the water temperature setting. Ask whether the valve can be set to limit hot water. If your parent works with a therapist or occupational therapist, ask them to look at the plan. If your parent has a doctor, ask whether there is anything about bathing safety the doctor wants noted. This is a practical check, not a medical judgment, and the decisions stay with your parent and their care team.
Get two quotes on the same sheet
Send each contractor the same written scope sheet. Ask each one to answer every line, including what is excluded. Compare the warranty terms and the leak clause as closely as the total. A lower total with a shorter warranty and no leak clause is not the cheaper job. Ask each contractor for references from finished installs and whether you can see one. Notice how they answer your questions before the job starts. Slow answers at the quote stage usually stay slow once the work begins.
Put the backup plan on paper
Write down where your parent will bathe while the bathroom is torn apart, how long the contract says the work will take, and who will help with transfers during that time. On the same page, keep the contractor's name and phone number, the warranty claim number, the permit number, and the manufacturer's model number. Put a copy with your emergency contacts. Once that page exists, you have a plan, and a plan is what lets you rest while the work goes on.
You are allowed to ask for every term in writing and to wait until you have it. If you are in St. Louis and want local places to ask about support during a home change, start with Local Help for Caregivers in St. Louis.