hmm..try altcoin solo mining!
My suggest :
Build private mining pool (I using MPOS), so u no need to buy any miner and no need to pay electricity cost, u can rent hashing power (at nicehash, westhash etc.. ) as long as your diff setting is right
Do some research on altcoin before mining, this is the factor u need to know on ur research
- Block reward
- Net hashrate / Global Hashrate (rent half of global hashrate is nice

)
- Coin price in Changer ( also buy support )
- Block Time, for make sure try to find block explorer so u can see how much block resolved per hours
- Renting price
- etc....

cheers!