burst.net is the most cost efficient.
The 9.99/month will run 2 bots. First package is not reccomended.
Virpus i've heard is good as well but haven't tried it myself.
But they will lag. The only real upside to using VPS botting is you save electricity (which depending on how long you bot may be way more than a VPS will cost you) and that it has very large bandwidth (for people with shitty ISP like me).