Will someone please point me to the section of Reg Z that says the monthly HELOC statement has to include the Maximum Line Amount and the Available Credit Amount on a HELOC loan?

I don't think that's necessarily a requirement, or at least I couldn't find it when looking in 1026.7(a).

This information is listed on Model Form G-18(F). However, certain items listed on the model form are not required per the commentary it states:

"The summary of account activity presented on Samples G–18(F) and G–18(G) is not itself a required disclosure, although the previous balance and the new balance, presented in the summary, must be disclosed in a clear and conspicuous manner on periodic statements."

It's possible that someone is taking everything listed on the model form as being required. You may want to point them to the above statement in the commentary.

Isn't that the model form for credit cards?