Shiner, I take your point. However, it's not practical to keep two sets of records. Should he enter the new job at No.45 in both programmes and make a note of when all the jobs he has just done are next due? Keep a backup of whatever programme you are using and if you decide to change, well then you have some work to do, but at least you have all the info available.
I only meant that the customer list could be kept that way. No need to worry about record numbers as a database will quickly sort that out if a sort is required.
For instance, in my MSWorks database I have the following fields (amongst others):-
<title>,<firstname>,<lastname>,<address1>,<housename>,<housenumber>,<roadname>,<town> .
If I want to sort them into order I use the sort parameters <town>,<roadname>,<housenumber>
Doing something like that completely alters the record numbers anyway.
The other main sorts I do are called <nearlydue> and <moneyowed> which are self explanatory.
If the time and effort is put into setting up a database at the start, it can make life a lot easier as the business grows. Of course if extra things are needed, more fields can be added later. I have 23 fields in my main database which do a number of different jobs. It sounds complicated but I wouldn't want to return to the way I used to do things as it's fairly simple to maintain if updated for a few minutes at the end of a days work. Those 23 fields were not there from the start. Many have been added as I have adjusted the way I do things. Indeed, some of them are rarely used.