if u dont trust your own people then lock them out and learn how to program yourself. if u dont possess the technical skills to manage a programmer then use prebuilt software and give limited access.
for example, if you had a
PornCMS hosted site, your programmer would only be in the templates and/or content areas. he wouldn't be in your billing account or the server files.
if you can't use prebuilt software, then hire a company, not a solo programmer.