MS Access / BDE Question

Dear All,

  A friend of mine has some business-related info contained in an Excel
spreadsheet and is thinking of importing it into MS Access.  He wants to do
a few things with it, like sort parts from a list and help narrow items down
to appropriate suppliers, so he can create purchase orders, invoices etc
from the spreadsheet.

He also has an existing MS Access database for customer records that he also
uses and an address book in MS Word that he uses to print labels and
envelopes.  With all these apps open at once his PCs are slowing down a tad.

I've suggested that he could have all this info available in one custom
application using the Borland BDE.  He is keen to start off with having the
Excel stuff using a new front end and then maybe later adding the other
database stuff from Access and Word.

He also needs to be able to have more than one user at a time access this

From how I understand it, it should be possible to merge all this data into
a single MS Access database and either generate forms and reports etc. (all
within Access), or access the database from a separate Delphi / C++ Builder

What I'd like to know is the general pros and cons involved with each
option; things like, would there be problems involved if different users run
different versions of Access?  Is either one of these options likely to be a
heck of a lot faster or secure than the other?  Is it going to take way
longer to write the third-party app, even if I were to use the BDE?

If anyone can give me some pointers on a project like this, I'd appreciate