Any agent that has ever worked on a short sale has asked the same thing. It's a painful process as the bank collects financials from the seller, price opinions from other agents and discusses the options with the investor. The usual wait is 3-6 months with some going even longer. You can't lock your interest rate because you don't know when it will close. Unless you found a "pre-approved" short sale and offered the suggested price, plan to wait.
One bit of advice while waiting, keep your eyes open. If you see another house you like in an acceptable price range talk to your agent about your options.
When I am working with buyers, I encourage them to write an offer on a short sale if they like the home, but don't rely on it. Keep looking. In this day and age, I will oftten write multiple offers for buyers and in the end we see what comes back.
It's complicated - but I just don't recommend putting all your eggs in one short sale basket!!
This is information you may have benefitted from having prior to going to contract. At this point it may be helpful to have the answers to these questions before commiting long term to this transaction:
1. Have the sellers provided the necessary "short sale" paperwork to their lender?
2. Have the sellers submitted a "letter of hardship" to their bank?
3. Has a "loss mitigator" been appointed. If so, request their name and contact information.
4. Does the lender appear willing to work with the owner on a "short sale?"
5. Are their liens on the property?
6. Are their multiple mortgages or loans attached to the property?
7. Has the bank ordered an appraisal of the property?
8. Has the bank agreed on an acceptable selling price?
Putting you agent to work obtaining this information may help you determine if the time invested is going to be work the wait.