There is in my way of thinking a few ways to part with $3K.
1, Buy Branded New Off the Shelf products produced to a very restricted build budget, where the end product will produce music, but it won't be very refined. The search to create a system using this method that will recognised as surpassing other systems produced using the same Purchase method will be long.
2, Buy used, there will be more info available on products from a broader fields of information. Both Reviews from when a new launched product and user reviews will help shape an idea of what might be expected if a demo' could be had. Using this as a Purchase method will get one closer to owning Amp's to be used in a system that may have cost close to $6K if a a few years used. Additionally, there may be recognised mod's for certain devices that assists with refining the sound being produced, and maybe puts the model in a more attractive option than a model that superseded it from the Brand.
3, Buy into a purpose designed Brand, where the product is directed at the DIY community, much of the outlay will be for a Bill of Materials, that would usually be the type of BOM for Amp's costing substantially more. A Neurochrome or Bruno Putzey Design, Purifi EIGENTAKT Class D Amplifier falls into this camp, to buy into Amplification to show such models a clean set of heals is not easy.
I have been demo'd as part of a Group, Neurochrome Power Amp's using a Soulution Pre' in comparison to a Soulution Power Amp', with the assessment from myself as well as the Soulution owner being gobsmacked how good a Amp was which was costing £47Kish less.
With proper investigation and choosing carefully a method to achieve an Amp' type suggested in option purchase method 3. Both Amp's of Interest, Pre and Power may be achieved at very close to your Budget.
I am familiar with very capable Pre' Amp's that can be purchased using the method 3.