There are a couple of significant obstacles to buying 2nd user machines.
If not buying from a broker/dealer it can require a bit of luck to find the machine you are after when you need it, middlemen might add cost but they can also reduce risk.
Even quite successful companies tend not to have $$$ of cash sitting in their bank accounts for capital expenditure and even if they did it isn't always tax efficient or wise to spend it all on capital equipment.
Finance companies and Government grant schemes often do not support the purchase of 2nd user equipment. (they might however allow for factory refurb to "as new").
The OP is looking for a machine as a step-up from manually soldering 0603, pretty much anything is a step up from that. New machines are a big investment and its important to choose the machine that fits the way you work as well as how you might work in the future. Having a machine like that will alter your designs as you realise what you can do and exploit its potential further, however while Yamaha Machines are excellent, I think they are perhaps a step to far to start with, plus depending on what your designs look like you might even end up wanting two to get the feeder space. I would look at the smaller machines first, you can do things with standalone machines like the TWS (or Autotronik or Essemtec or ID or Fritsch if configured without a conveyor) that big in-line machine cannot. That can include putting trays (including strips of tape) in the placement area with the PCB without losing feeder space, loading & building multiple designs at once & managing boards that the designer has forgotten important things like borders and fiducials on.
I would look at Fritsch, Autotronik, Heeb?,Essemtec and TWS, first they will cost you less and take up less space.
Moving up a little another strong machine is the Europlacer IICO, the flexibility on these machines is pretty much unrivalled, it's no speed demon but you could keep a sizeable proportion of your stock on up 198 lanes ready go on the machine at the drop of a hat.
Next port of call might be the Europlacer IIneo or Mycronic MY300, however I'm not sure exactly what the pricing on these looks like when you get a real quote on these anymore as they have both had recent updates and my old quotes had BIG discounts on them.
After that I think you end up in your Yamaha territory, there have been a lot of mergers so there less to choose from than there were but you still have Juki (now includes sony), Hanwha (samsung), Kulicke&Soffa (assembleon), Mirae, ASM (Siemens/DEK) & Fuji.
K&S I think you can ignore, ASM have the "E" series, the rest you can ignore. Everyone else has a range of machines all of which should be comparable in price to the Yamahas where I would be looking at the Ipulse M10/20. I would look at all of them at least at the brochure level, you can learn a lot just from the features they choose to highlight.
Of course I have left out two US brands Universal make some awesome looking machines and then there is Versatec who might sell something called a C5.