A floor survey first
Elevations are taken through the house so the low areas show up as numbers. Without that, a crew is guessing at where to put piers.
When part of a concrete slab settles into the clay, the walls, doors and brickwork above it move with it. An independent provider can measure how far it has gone, work out why, and support the slab where it actually needs it.
Most Arlington slabs were poured from the 1950s onward, and almost all of them sit on Eagle Ford or Blackland clay that swells in a wet spring and shrinks through a drought summer. Movement is normal. Movement that keeps going one direction, season after season, is the part that needs attention.

Not every job needs everything below. Ask the provider to separate what the slab needs now from what is worth watching, and to say which is which in the quote.
Elevations are taken through the house so the low areas show up as numbers. Without that, a crew is guessing at where to put piers.
Drainage, tree roots and leaking water lines under the slab all cause the same symptoms. If a plumbing leak is suspected, that gets tested before anyone lifts anything.
Piers go along the perimeter beam and, where needed, under interior beams through tunnels. Placement follows the survey and the structure, not a standard spacing.
The slab is raised in stages while the crew watches the doors, brick and sheetrock. Access holes are backfilled and the site is cleaned up before the walk-through.
The quote should state where each pier goes, how many there are, what type they are, how deep they are driven and what happens if the crew has to go further. It should also say what is not included, which usually means the cosmetic work: sheetrock, brick pointing, door adjustments and flooring.
Which pier suits your house depends on access, soil depth and the weight being carried. Read the pressed concrete versus steel piers comparison before you decide, and see how piers are installed for the mechanics.
If the survey shows the slab is still close to level, the better money is often spent on drainage and root barriers to stop the cause. Once the slab is supported and settled, the visible damage left behind is dealt with under foundation crack repair. Not sure yet? Start with a measured inspection, or check the nearby areas.
Mainly the number of piers, the pier type, how deep they have to go and how hard the access is. A perimeter job on an open lot is straightforward; interior piers reached by tunneling under the slab take longer. Ask the provider for the figure in writing after the survey, not over the phone.
Some close up as the slab comes back, some stay. Lifting is done to get the house stable and as close to its original shape as it will safely take, not to make every crack disappear. Cosmetic repairs are normally arranged separately once the movement has settled.
It happens often enough that it is worth ruling out. A line leaking under a slab keeps one patch of clay soaked while the rest dries, and that difference moves the slab. If the inspection points that way, a pressure test comes before any lifting. See what the inspection covers.
No one honestly can. Clay keeps responding to weather, and the aim is to support the house so that movement stops causing damage. Ask the provider about any warranty terms in writing, what they cover and whether they transfer if you sell.
When you call, describe what the doors and brickwork are doing and when it started.