I think there might be some overestimation on just how difficult and unbelievably expensive it is to build a turbine engine that has the ability to safely fly over civilian airspace to deliver goods. There are military drones which have scaled down turbine engines, I would imagine this one would be slightly smaller then those, but here are some things to keep in mind.
Before I became a software engineer, I used to work in aerospace and defense dealing with everything from missile systems to a large variety of aircraft components. You could face serious issues and even potential jail time if you are not extremely careful about the parts you purchase.
people don’t realize that what seem like common commercial parts, even some such as nuts , screws, and fasteners, may be under ITAR military regulations and are forbidden for personal use. Turbine parts are specifically made to withstand extremely high stress and temperatures so they are legally classified different ways, mostly due to the fact that many of the parts that go on commercial jets are the same ones that go on military jets.*
Unless you are a certified FAA or if in Europe , an EASA repair station for aircraft you would be surprised how difficult the simplest parts could be to get, let alone getting fan blades.
Be very careful about buying parts from brokers type distributors online
Cost / Purchasing / Safety
Don’t forget safety, money has to be spent on special coatings and treatments, if components do not receive them,
they will likely fail, and without proper safety, equipment, and test grounds, chances are someone is getting killed.
It would be a lot easier to purchase needed materials if you started a business and incorporated.
However these parts are not cheap, unless you are doing production run to make a couple thousand engines, your costs depending on complexity/scale could be anywhere from $500000 to easily over a few million once you add in costs for custom manufacturing, coatings, cost of shipping components out to test labs and back, the very high cost of testing at the labs for certain components, fuel costs for the insane amount of test hours needed, etc…
And don’t get me started on a test facility, if this thing is flying in civilian airspace to deliver, then you must physically recreate conditions like the engine being able to withstand anything from a few small dead birds being thrown in it, to dozens of gallons of water , to ice balls, to tons of sand and dirt (its why those parts cost so much money and need to go through extensive expensive testing) anyways, building this type of facility or somehow renting one is not going to happen unless you win the lottery.
I love the enthusiasm in this project but knowing certain facts it would seem to make more sense to pivot to an idea which is slightly more feasible.