Super-Manual recommendations [$500 - $1000]

​I have a very specific need in a machine. I am looking for an affordable option for R&D for a future cafe truck. I want to not only learn to make extraordinary espresso, but also want to experiment with settings and experience for myself what different setups do to a pull. my only experience with making espresso is with fully automated machines.

​my ideal would be the Rocket machines, manually adjustable everything, but for less than 1000 new. I do not want a lever machine though, it should be able to pull double shots and should have a steamer too

​thank you for any help or direction!!