I am assuming that at this point you have never put a straight razor to your face and taken your first stroke.
If that is the case, then you are enthusiastic about this art but don't yet know if it is for you. But you are thinking "If it turns out I love it, I don't want to have to invest in an upgrade from a starter set in 3 months".
So here is MHO. The razor and the strop are your first and main investments that affect the initial success/failure of the shave. Your brush, soap and mug all affect the improvement in the shaving experience.
If you have the money and want to get everything in a kit - do so. But if not, get the SRD DOVO Special and Strop combo and get the VDH soap Brush Combo ($10.00 as Walgreens) and a coffee mug. That is enough to tell you you love or hate the art.
Also, you really will end up with two razors as your baseline. The DOVO
Special 6/8 is a really fine razor. I just used mine yesterday and had forgotten what a great shave it gives. So that is not a beginner razor. It is a razor for your entire life. It can easily be one of your two baseline razors.
So I hope that helps a little. The decision is still a personal one.