Both front lower control arms on the Model 3/Y are prone to the rubber bushes tearing or delaminating. There's a lot of force going through these bushes and the range of movement they have to deal with is part of the issue. If you only use your car in town or on good quality roads, or you drive like Miss Daisy, they'll last for years but for a lot of us these arms are going to need replacement every few years unless you upgrade them to something like Powerflex poly versions. Even going to metal spherical replacements isn't going to sort it forever as they wear out too.
My advice is if you are coming out of warranty soon, get all the suspension arms and knuckles examined as some may already be torn or worn enough to need replacement. If you're out of warranty, there are lots of choices in the aftermarket now, but I'd avoid anything that looks too good to be true price-wise and anything from no-name Chinese factories. Cleevely supply good quality OE-spec. arms made in Denmark, which are a very fair price.
Replacing any of these front arms does not mean you'll have to pay for a 4 wheel alignment. At the very most, you may have to have the front tweaked, but you shouldn't be paying for a 4 wheel alignment anywhere. Take it to a decent indy who should charge you a small amount to check and then price accordingly depending on the actual work carried out.
In any case, you can do the service test yourself for nothing to see if any alignment is required. It's called the EPAS test and is in the hidden service menu.
As costs are being discussed a lot in this thread, here are the Tesla Model 3 parts costs as of a couple of weeks ago:
All prices ex-VAT
Front Upper control arm (new version to fix the ball joint issue) £65.63 each side
Front lower compliance link £135.63 each side
Front lower lateral link £188.43 each side
Model 3 Performance brake parts:
Front discs £125
Rear discs £95.98
Front pads (axle set) £166
Rear pads (axle set) £310
There are some other additional parts needed which would add a bit more to this (springs, caliper bolts).
I just ran an estimate for all discs and pads to be replaced by Tesla and the total came to £1273.03 + VAT.
You can't get front M3P discs from anywhere other than Tesla currently. It's a bit easier for the M3LR, MY and MS/X as the calipers are used on other makes/models. Beware of typos on many motor factor websites. There are a lot of websites claiming to offer M3P front discs, when they are actually M3P rears or M3LR/SR discs. Same with pads. Even the likes of Brembo, who make them, have typos on their website!
But, as pointed out to me by M00cow, Cleevely do offer M3P pattern pads and rear discs and everything for the other models and you can save a lot of money if you go with those parts.
The work involved to change anything to do with the brakes or suspension arms is not at all difficult. If you have done car maintenance before you could do this. Any garage worthy of your business can do this sort of work. No special tools, diagnostics or ADAS calibrations required other than what you could do using the service tools built in to the car's software.
Hopefully that answers some questions but ask away if you have any more!