Drip Irrigation System for 20 - 50 plants?

[jtjmartin]

I graft most of my tomatoes and they get planted in ground. Every year, I have varieties that I really want to grow, but the grafts just don't take.

Next year, I'd like to add about 20 non-grafted tomatoes to the mix using grow bags. Being a compulsive tomato grower - this number is likely to increase to 50! I'll use my same lean and lower system. The weakness in my plan is watering the tomatoes in the grow bags - I often travel for a night or two.

What irrigation system and timers work and are cost effective for small scale growing?