Have a room, ~10x10 that I want walls to be waterproofed and durable. This room will have parrots in cages. Cages will be periodically hosed off (have concrete floors, floor drain). There wont be intense water on the walls every day, like a shower, but there will be times it will be sprayed. Durable is because if they get out, they will destroy! : ) Have contemplated hardi-plank (or comparable), Durock, tile. I think tile could work well but the expense!!! Currently walls are framed. This room will be climate controlled. Maybe someone has other ideas?
Remember that concrete is porous so even if you have a floor drain some of the moisture will seep into the concrete. Seal the floor with a penetrating sealer or an epoxy floor paint. Maybe even an elastomeric membrane you paint on before applying tile on concrete slab floors. RedGuard is one type of product.
Your best solution would be to build the entire room like a shower like you mentioned. Moisture barrier on walls that extends a few inches on the floor and is sealed to it. Cement board or hardibacker covered in tiles. If you look around you can find cheap tiles. There are tiles stores around me in industrial areas that advertise $1/sq ft tiles. Home Depot has a 4x4" tile going for $0.16 each.
If the tiles are too much money...
If appearance isn't a concern maybe you can just paint over cementboard walls with the elastometric membrane?
Also Quikrete has a waterproof cement product called QuickWall Surface Bonding Cement. It's main purpose was to parge over dry stacked concrete block walls but it's also used for cisterns. You spread it on with a trowel like stucco 1/8" thick. At 50 sq ft per bag it comes out to about $0.32/sqft.
I've used it and it really is waterproof. I painted over it with DryLock waterproof paint for a nicer finish. I spoke with Quikrete and they said the DryLock wasn't necessary but already had it and I wanted a smoother surface on the wall. You could probably just use a regular, mildew resistant, glossy paint instead. Call Quikrete and see what they have to say because it's been a while since I used it. You'll want to let it cure a bit before
I mixed it up I think 1/2 bag at a time in a 5 gallon bucket with their acrylic fortifier using a drill and paddle mixer. Spread it on using a cement trowel.
There are hard plastic sheets for covering walls - often seen in commercial food preparation areas (easy to clean.) Similar in format to "tileboard" but solid plastic all the way through, (tileboard is a cheesy tile substitute that's basically masonite with a fake tile surface - it might work for you too, but I would not recommend it, given the desire for durability and serious washdown.)
One possible approach if you can't find exactly those at a reasonable price locally would be to use good old fashioned formica (plastic laminate)- you can still easily get large sheets of that NOT already attached to a preformed countertop, even though the preformed-countertop version has dominated retail home improvement for a while.
Tile CAN be quite reasonable IF you install it yourself and shop around. It can also be extremely expensive if you become dead-set on something that you can't find a good deal on, or have someone else install it.
IME, the hardi or durock products are good as substrate, not so much as an easy-to-clean surface. However, there are a lot of different hardi-products, so I may be thinking of a slightly different one than the exact version you are.
In any case, consider putting up shower liner first, since you still have the walls open.
Using the wall panels that were mentioned before that I provided the link for, place that over a layer of 1/2" OSB, from the corner of the ceiling to the top of the Durock or Wonderboard that you will apply first. This cement board only needs to cover at the minimum the first foot of wall were the floor meets the wall and wicking can occur up from the floor when the walls are sprayed. The joints to the floor and between sheets are covered in fiberglas drywall tape and coated with modified thinset. let it cure for a day. The rest is the OSB plywood. The cement board is then covered with the liquid membrane used for showers that in now available at tile stores and even Home Depot if you like red. When you apply it, tape the floor to give a neat edge, for you will see this and it will look more presentable. Then apply the FRP (Fiberglas reinforced plastic) panels with their fasteners, and sealant applied where needed, joints screws, etc. The FRP panels are not set to the floor, that will promote moisture being trapped. Hold it up about 4" so it shows the Cement board, taped joints and waterproofing that has been applied over all the cement board.
Using 1/2" OSB will allow you to screw items that are light weight to the wall with the worry of finding a stud. For a cheaper way to do it wonderboard is available in 5/16" material and use 1/4" or 3/8" plywood or OSB. To hang objects you will need to find the studs for this.