One more thing to help you on your way, a basic chart to help you understand the basics of what you're looking at.

The grind is going to be personal preference, I prefer hollow grinds: while they're far more fragile and prone to chipping with the slightest mishandling, they get scary sharp, and the scoop the hair like a snow plow.
The width, the wider blades equal heavier blades and they tend to last longer since there is more steel to work with. Not much left if you chip a 4/8, but you can often get away with regrinding a new edge on a 7/8 (and they also often times are the more desirable and fetch a bit more money)
-the heavier blades work ideal for heavier, thicker, coarser hair. Like when my mane comes off, I'd go with a heavier blade, or trim it down with clippers.
-you know your beard better then i do, but I'd recommend staying away from the 4/8 for starters, esp. for a first razor, since they do have the least amount of steel, and ergo the shortest lifespan do to hone wear, would be a shame to buy one that looks ok, but turns out has nothing left to offer and has been honed to death; but 5/8 however can typically do very well for a daily shaver removing stubble, and i found you can find a lot of them with plenty of life left (+1/8 is actually a lot of steel when talking about basic honing and stropping), a good 5/8 is pretty standard and more then adequate for 90% of users daily needs.
-if you find something nice that's wider, considering the condition is roughly equal, wider is better.
I'm hardly an expert, more of a somewhat knowledgeable novice myself I'd say, but I'm sure now that the mods moved this to the proper forum, someone with more knowledge then I will be able to chime in with even more wisdom.