These are the articles to read before you spend anything. They compare the non-surgical options side by side, set out honestly where those options stop helping, and give you the questions that separate a clinical consultation from a sales one.
Every clinic owns a particular set of machines, and it is natural for a consultation to lean towards whatever is in the room. Reading these first means you walk in knowing roughly which category of treatment suits your skin, which questions to ask, and what a fair quote looks like.
The thread running through them is matching the treatment to the problem. A good device applied to skin that has stretched past its limit will produce a slightly firmer version of the same fold, and a course of sessions is a real amount of money and months of waiting. Knowing which side of that line you are on is worth more than knowing which brand of machine a clinic owns. For the practical side of vetting a clinic, the checklist on how to choose a clinic covers registration, devices, quotes and photos.