If you have a broken wheel stud, you can fix it yourself - no need to pay someone. As with anytime you jack up a vehicle, chock the wheels, set the parking brake, and support the vehicle with a jackstand. On to the procedure: Remove the wheel, unbolt the caliper and hang it with a wire from the spring (don't let it hang by the brake line), and remove the brake rotor. The studs press in from the back side of the hub - straight in, not screwed in. Put a screwdriver on the broken stud and pound it out with a hammer - it'll fall out the back side. Position the new stud from behind into the stud hole (line up the splines on the shaft of the stud with the grooves in the hole), and push it as far as you can. Now, stack some washers on the stud and then drive the lug nut onto the stud and tighten it as far as you can with the lug wrench - this will pull the stud through the hole. Remove the lug nut and if the stud isn't even with the others, put a few more washers on and do it again. Repeat this until the new stud is fully seated, and then put the rotor, caliper, and wheel back on. That's it - you're done.

place the hand brake on firmly--chock other wheels . loosen off the wheel nuts . jack the vehicle up finish removing the wheel nuts . pull the wheel of the studs . fit replacement spare wheel onto studs . do wheel nuts up as tight as possible . lower jack so that the wheel is on the ground . finish tightening the wheel nuts . Replace the jack and wrench in the boot along with the flat tyre . Take the flat tyre to a tyre shop for a puncture repair and have it fixed immediately. Most "people" leave the repair to a later time when they will need a spare that they do not have .The tyre change process is fully described in the owners hand book for your vehicle.

this is a very in depth procedure I do not recommend doing this if you cannot or have not taken a wheel bearing off. That being said this is how you do it:
after you have removed the wheel. remove the brake caliper from the steering knuckle* after hanging hte caliper in a safe location try to knock the stud through the wheel bearing**, if the stud does not come free of the steering knuckle then the wheel bearing must be removed, there are generally 3 'E-Torx' bolts that retain the wheel bearing to the hub on the steering knuckle ( you can turn the wheel left to right if need be but be sure that you have jacked up the entire front of the vehicle and that the parking beak is on and the wheels are chocked steady) once you have the broken stud out of the hub you then need to replace the new one. here is how that is done; set the new stud in place then apply a few large washers on the new stud that is seated in the hub. next thread on the lug nut and start tightening the nut down and draw the stud onto the hub, also it is a good idea to tighten down the stud backwards if it is through style lug, if not its no big deal either way, if you bottom out the lug you will ruin the chrome cap so it is a good idea to use as many washers as possible i usually use about 5-6, one inch washers for this procedure. be sure to check the " * " items at the end of these instructions. they will save ou time and trouble.


*YOU DO NOT HAVE OT REMOVE THE BRAKE HOSE FROM THE VEHICLE

** SOME TIMES YOU CAN ROTATE THE WHEEL BEARING AROUND AND GET A CLEAR AREA TO REMOVE THE WHEEL STUD FROM THE WHEEL BEARING WITH OUT REMOVING THE WHEEL BEARING ITSELF

I am assuming you are talking about a wheel lug stud. The lug studs are pressed in from the inner side of the drum or rotor or axle flange depending on how your vehicle is equipped. You have to remove the wheel and drum or rotor to get access to the back side. Drive the broken stud out from the front after you have removed the drum or rotor and set the new one in from the back and tap it into the hole until set as the rest are. If you cant get it set all the way you can finish setting it by pulling it into place when you tighten the lug nuts on reassembly. The part should be under $10.00

1. Step 1 Buy a new stud. Make sure you purchase the right size. If you're not sure what size to get, wait until you remove the stud and take it with you to the store.
   
2. Step 2 Check the area of the spare tire in the trunk for the jack and the jack tools since you'll need to raise the car to replace the wheel stud on your Focus. Be sure to block the tire diagonal to the jack.
   
3. Step 3 Use the jack to raise the Focus. Remove the wheel Take off the caliper and either hang it by a mechanics wire or lay it up so it doesn't dangle by the brake line. Remove the rotor. If you're working on back wheels, you have to remove the emergency brake clip first. You could have drum brakes in the rear. If they're drum brakes, remove the drum.
   
4. Step 4 Hunt for an opening behind the hub that allows you to remove the stud. Line the stud up with the hole. You may have to take off the hub and put it in a vise if you can't drive it out the back.
   
5. Step 5 Hit the stud with a mallet and drive it out the back of the hub. Push another stud into the opening. This is tough work, but you only need to push it far enough to thread on a wheel bolt.
   
6. Step 6 Put on a wheel bolt and begin to tighten it. As you do, the stud starts to pull through. Add more bolts as necessary until you seat the stud. Check in the back of the hub. When the head is flush with the stud, you seated it.
   
7. Step 7 Remove the extra bolts and reassemble the parts that you took off to replace the wheel stud on the Ford Focus. Put the wheel back on the vehicle and tighten down the wheel nuts.