If I were in your shoes, I would set up both FBA and FBM for every single product I sell. That's my first move, before I even think too hard about the costs or the specific 3PL I'm going to use.
My thinking, which is heavily shaped by listening to Bradley Sutton on the Serious Sellers Podcast, is that this isn't an either/or decision. It's about building a resilient operation. In week one, I'd get the structure right inside Seller Central. I would literally create two SKUs for each ASIN, one fulfilled by Amazon, one by me. I might even ship the first few FBM orders myself from my garage just to understand firsthand what's involved in the process.
In month one, I’d use that experience to find a smart 3PL partner. I wouldn't just look for a company that does Fulfillment By Merchant (FBM). I'd find one that can also act as my central logistics hub. Burak Yolga made a great point on an episode of Serious Sellers called "Tips To Save Money On Your Amazon Product Shipment and Logistics" that has stuck with me. He advises shipping your inventory from your supplier to your 3PL, and then dripping it into FBA as needed. This strategy gives you so much more control and protects you from the notorious FBA check-in delays, especially during Q4, and ever-changing inventory capacity limits.
What I'd actively ignore is the idea that you have to choose one path. So many sellers frame it as FBA vs. FBM, but the smartest ones I see are doing both. I'd also ignore the myth that FBA is automatically cheaper or better. Manish Chowdhary often points out on The Smartest Amazon Seller that once you factor in storage fees, removal fees, and placement fees, a 3PL can be very competitive, particularly for certain types of products. The best part of the dual-SKU approach is you can offer both and let the customer decide. Some will happily wait an extra day for cheaper shipping.
The biggest trap you can fall into is 100% reliance on FBA. When your inventory is all tied up in Amazon's ecosystem, you're completely subject to their rules, their delays, and their fee structures. If they lose a shipment or decide to transfer your inventory between three warehouses over two weeks, your listing is effectively down and you're losing sales. Having that FBM offer active, fulfilled by your 3PL, is your insurance policy. It keeps the lights on. It can even evolve into a real strategic advantage, especially with programs like the new Seller Fulfilled Prime.
