Concurrent accesses - Mac (or PC) - 5 users

Hello All,

I swiftly went through the site and the wiki but I'd like to get
your opinion before going further.

- I want to set up a small database with less 1500 clients and
related data, 5 users.
- All 5 users will get on their machine a software I am writing
in python (+wxpython) to access and manage the database.
- Machines for users are Mac (OS X).
- There are small but NOT NONE chances that several users would try
modifying the same clients on the database at the same moment.
- The database file would be owned by one of the machine (they are not
overloaded...) and accessed through a small network.
Or possibly if necessary on a dedicated Mac or PC.

I have read that there may be problems due to file-locking system
weaknesses / failures.

Questions:

1) What do you advise me to do ?
Can I contemplate using sqlite for such an application.

2) Is there an unacceptable probability that we would get problems with
simultaneous acesses ? (for me, once a year with an easy fix process is Ok.
Once per day is not....)

3) In case of problems, what happens then ?
Is the database file irremediably lost ???
Or is there an  easy repair process ?

4) In case it would be ok for working with sqlite in this case,
can you give me some hints and possible web links to take care of
access problems or whatever important matters when developing my
python stuff.

5) Or would you advise me to go for something else (Postgresql, mysql...)?

6) Would the answers be the same with users and database working with pcs.

Thanks a lot for your answers
Dominique