Most items have been covered in the preceding posts but to elaborate, in NSW any Fees & Charges raised by your Plan’s Strata Managing Agent are shown in the Agency Agreement that your Owners Corporation has with that Agent, and the method of their application for debt recovery is usually provided in a Motion submitted by the Strata Manager for consideration at each Annual General Meeting of the O/C.
You should make it your business to know what your Plan’s debt recovery procedures are, and that’s why your O/C (of which you’re a member) needs to agree to the amount/s of those Fees via its Agency Agreement, and via a Resolution taken at a General Meeting of the O/C with regard to how those procedures will implemented for those Proprietors whose payments are in arrears and at what intervals (e.g. 30 & 60 days after the due date) they’ll be applied.
As the Secretary & Treasurer of a self-managed Plan I must admit that I don’t have a lot of sympathy for Proprietors who don’t pay their Levies on time, but in answer to your specific questions, the interest that an O/C can charge is restricted in that it can only be applied to Levy payments, and only then to amounts in arrears at one calendar month from the month in which the payment was due, and at 10% interest (simple).
So your Plan’s Strata Manager cannot charge you interest on the collection fee component of your debt, that debt for fees alone does not make you un-financial in terms of you voting at General Meetings, but your Strata Manager may, under the O/C’s Resolution that I’ve referred to, engage the services of a debt collection agency on behalf of the O/C whose fees will be added to your debt if/when collected.
With respect to your Executive Committee waving those Fees, they’re not the O/C’s Fees to waive they’re the Strata Manager’s Fees incurred in doing the O/C’s business, and so far as the interest on any unpaid Levies is concerned, that can only be waived by a Special Resolution taken at a General Meeting, not by the E/C Chair or by a vote of its Members.
If the matter proceeds to the Local (small claims) Court, there’s a well established precedent that it will only award debt collection fees against a Proprietor if the Strata Manager can justify that the amount of the Fees was an incurred expense (i.e. in collecting the debt), but I’d suggest to you that a large Agency such as the one that you’ve referred to could probably make that justification.
After all that, in my opinion a reasonable way forward for you would be to ask your Strata Manager to check that the calculations of interest has been applied only to your Levy payment arrears beyond that one month period (if it doesn’t already) and at the prescribed rate (10%), to then pay the full amount owing, and to either make a note in some reliable way about when your Levy payments are due (same date) each quarter or ask your Strata Manager to send all future Invoices to you by e-mail.