So I am able to get a 4' 8 bulb t5 system for 50$, veging bulbs included.
That's a good price assuming the bulbs don't have a ton of usage (they lose lumens over time). If you're growing shorter plants (autoflowers, scrog?) it would work ok for you but you'd need some warm (3200-3700k) tubes for flowering.
For taller photosensitive plants, not fimed, scrogged, etc., T5HO doesn't have enough penetration. You'll still get some good bud. I grew 5 plants under T5HO and it produced pretty good. But, not as good as a light with more penetration.
For that price you could try it and see how it works. Be prepared to add some CFLs or a couple LED UFOs to supplement in flower (if they're tall plants).