Every collision is slightly different and down time always depends on the extent of damage. A small repair with minor paint work will usually take 1 to 3 days minimum. While heavy damage may take much longer. We will be able to give you a very good idea once the estimate is written..
Obtaining 3 estimates is not necessary, unless it is stated in your policy. If you are a claimant you only need an estimate from where you choose to have the vehicle repaired.
You can go to any repair shop, unless your policy specifies a list of repair shops to visit. Again, if you are a claimant it is entirely your choice where to have your vehicle repaired.