I would go dump truck for sure. I would not bother looking at 450 or 550's. I would take a look at international 4000 series, we have 3 86,92,98. Cheaper to buy,maintain, pto pump(huge plus) and be able to haul load plus pull a trailer.
I have always been 100% landscape and excavating, wish someone would have gave me this advice earlier on in my career.