Litecoin's total hashrate is aroun 2 THs (Scrypt) (2000 ghs or 2 mil Mhs).
To try solo & get profit; you should have at least %1 of the total network hr, so 20 Ghs is the min for it. (Unless it won't be profitable.)
But if you feel lucky you can try with 300 mhs.
Yeah i rented about 2ghs but didnt found a block sadly.
Im mining for the last few hrs now in litecoinpool.org
i should have done this from the beginning
Somehow i like LTC way more than BTC.