I know I would have received several very large bonuses on top of a land grant, plunder, and my regular pay. As a veteran, my loyalty would have been a valuable commodity during the civil wars.
If I managed my money well, how well-off would I be when I decide to hang up the gladius?
EDIT: If I didn't have enough service to be discharged by Julius Caesar, pretend I enlisted before 58 BC
To those leaving comments about how there are so many deleted comments: Stop it. You're making it worse. Now in addition to having to remove unacceptable answers, we're also having to remove your comment. Over half the deleted comments on this thread are people commenting about deleted comments.
Seriously. Stop it.
Well, if you played your cards right and backed the right people (Julius Caesar and Octavian/Augustus respectively), you could at the very least count on having a substantial plot of land in Italy, Hispania, Gaul, or Greece. Faulker notes that at the start of the Pax Romana there were at least 300,000 farms owned by Caesarian veterans in Italy alone, and these lands were coveted by many.
You seem to be suggesting, however, that a scrupulous legionnaire who only stuck to the right campaigns might have made out like a bandit -- this stands to reason, the sack of Alesia especially yielded a substantial amount of plunder. However, a common soldier's share of this was probably not impressive -- Caesar kept the lion's share for himself and his officers.
I can't tell you how rich a soldier might be after surviving the bloody death of the Republic, but I can hope to provide context. Based on my admittedly inadequate review of sources, it seems that even the most successful of soldiers couldn't acquire enough wealth through plunder and their regular salary to compete with Senatorial or equestrian wealth -- there are few, if any, records of ordinary soldiers rising above the status of yeoman farmer. If you managed your money well, it seems the best you could hope for is to be comfortably upper-middle class.
I have, however, had a little bit to drink, so I might be overlooking something.
Sources referenced:
Neil Faulkner, Empire of the Eagles
Boatwright et. al A Brief History of the Romans
And a bunch of tabs I accidentally closed containing articles I am now too tired to retrieve.
Just to tag on another question (or two (or three))
What WAS the currency of the Roman Republic/Empire?
What would be the "exchange" rate of the Roman currency to today's value?
For the sum of money stated for the above question, how much would that be worth today?
Followup questions: How would such a soldier have kept his wealth, assuming he was frugal and wanted to save for retirement? Would he have had to actually carry gold coins around, or find someone he trusted to keep them for him? Could he have invested the money and grown it that way, and if so, what kind of investments were available?