First find out exactly where they are stiff, then loosen or lubricate that area.
You fix a broken bike with no wheels by looking for old parts that you can use to complement your seat and brakes. You should look for old parts in the newspaper.
You would need a screwdriver & a wretch to fix your bike front & back brakes. They are very easy to fix if you know what you are doing. So if you don't know what you are doing find someone that does or watch online videos.
Yes and any and all cars brakes get stiff or stop working when they wear out
The best place to go for your fix on brakes can be determined by finding the level of service of the different shops or mechanics in your area and finding the right one.
depends on the bike and the brakes. Go to www.parktool.com or www.sheldonbrown.com for more.
Disc brakes and drum brakes.
if your bike is a u, v or disk brake the cable is probably to tight or if you have hydraulic brakes of any kind your brakes will do this you just have to deal with it
any bike store
it depends how bad the damage is. If the frame is bent out of shape it would be better to buy a new one but if it's a minor problem like brakes not working or punctured tyres and broken wheels you should just try to fix it.
how do you fix the bike in my sims agents
Mechanical disc brakes.
Yes