The AMI says procuration fees must remain a remuneration option when the FSA sets its final rules for the mortgage market next month.
In its response to the regulator's Mortgage Market Review (MMR), the trade body repeats its stance any decision on remuneration must be agreed between the customer and the adviser.
In May, the FSA hinted it may scrap the payment of mortgage proc fees and introduce adviser charging instead in a bid to stamp out product bias.
But AMI director Robert Sinclair says: "Flexible remuneration options benefit consumers.
"A one-size-fits-all approach cannot be of benefit to people with drastically different financial circumstances and is likely to limit access to advice.
"With this in mind, we support FSA in not introducing alternative charging models into the mortgage industry."
AMI also wants the FSA to recognise the fundamental differences between fast-track and self-certification mortgages and ensure fast-track deals, which are appropriate for low-risk consumers, are not banned.
Sinclair adds: "Fast-track options should not be arbitrarily lumped together with self-certification ones. FSA must recognise the significant difference between the two models and therefore recognise that all consumers do not require the same level of checks."
In its response, it also asked for lenders to retain ultimate responsibility for assessing affordability and welcomed the FSA's view that the introduction of product regulation on LTV and LTI ratios is not necessary.
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