We have parameters as to how much fat can be liposuctioned in a single surgical procedure. In terms of the amount surgically resected during an abdominoplasty, this is individualized to the patient's needs and there are no legal restrictions on the gram weight to be removed.
In the US the standard limitation for liposuction alone is 5 liters. Some states have lower limits, sometimes 4 liters. Others limit the liposuction amount to 1 liter if additional surgery is done at the same setting. As to tissue removal for a TT, there really is not an accepted limit. The amount depends on preop anatomy. I have taken as little as a few hundred grams, as much as over 20 kilograms. The size of the patient may contribute to added risk, but the amount resected does not. All the best.