Ruby-on-rails website and MySQL support

I have a client with a Ruby-on-rails website which the previous developer has recently migrated to a new host. The site is working except for the user login, which has previously worked fine. There are a couple of other minor areas that need looking at as well.

Unfortunately the developer is currently unavailable to help (which went down well with the client!) and the cleint is desperate to have these issues fixed ASAP.

I do know the client is looking to revamp the whole site later in 2012 which I will need a designer and developer at that point, but if you can help out now that will be much appreciated and looked on favourably by the client when the revamp occurs.

The work will be as follows.
1. Confirm all the source code is available.
2. Investigate and provide a fix for the login link failure.
3. Investigate and provide, if possible, a fix to login using facebook ID
4. If time allows, discuss other minor issues and investigate and provide fixes.

We are looking for a fixed price to cover at least steps 1-3 above.

Please help if you can!