Hi vijay
I would honestly keep the preamp seperate from the streamer +dac. I've owned atleast 2 highly regarded dacs, with inbuilt separate analogue preamps. But adding a separate preamp, really added a noticable benefit. I even tried a lumin with the leedh volume control, but the scenario was different, with too many variables, but I was still not convinced. My own 2 cents, would be to get a dac cum streamer within your 3.5L budget, and then add a dedicated preamp in the future.