1. You can tell by the database file extension if it is the editable Database you are getting [in Access 2010 the extension is .accdb] or an un-editable executable [.accde].
2. To know if you have the editable Database, you can hold down the Shift key and open the Database and it will open in 'Design' view [which allows for changes to be made]. You cannot open the executable in Design View.
3. Unfortunately, it IS possible for a malicious person to put malicious code into the Database.
You need to be confident in the person you hire and YOU must MAKE SURE that she/he is dependable.
You could ask for a Resume and References like hiring Companies do.
Basically, it is your duty to yourself to make certain that the person you hire is trustworthy.
4. You don't have to be an Access programmer yourself. As long as you have the editable Database, you can always hire another programmer if at any time you are not satisfied with the programmer who initially does your work for you. That's why you have to make sure you are getting an editable version.
I hope this helps!
