For $30, I'd want them already fully identified and attributed, and in reasonable condition. Cleaned but unidentified Roman bronzes like this should be around $10 to $15, uncleaned coins half that again. FORVM sells bulk uncleaned Romans for $3.50 each.
The coins in the cleaned pic are all what are known as Late Roman Bronzes. Some of the earlier ones were originally issued with a thin layer of silver, which rarely survives being 1700 years in the ground, and almost certainly wouldn't survive the harsh cleaning this seller seems to prefer.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis