The current "PIVX Masternode Payments Information V1" on http://178.254.23.111/~pub/DN/DN_Info.html says following:

Reward from last Block for Miners/Stakers: 6.62 PIV
Reward from last Block for Masternodes: 6.88 PIV

1. If I Stake 30k PIV on 1 normal Wallet, can I then expect to get daily 19.86 (3*6.62) PIV?

sorry i dont know

2. If I have 3 Masternodes, can I then expect to get daily 20.64 (3*6.88) PIV?

yes but the numbers can change at any time -> seesaw mechanism -> amount of nodes online. but you can calc. with the numbers you see on stat. page fine

3. With which method (staking/masternode) is the chance higher to get the above stated rewards?

i guess with nondes you can calc. better but not 100% sure

Thanks for your help!