1) you only need to have one local controller wallet.  On the vps, you can either use multiple daemons (craved, craved2, craved3, etc), or use the same one.  In either case, you will just need separate folders that contain the configuration files and wallet.dat.  For example, you would have .craveng .craveng2 .craveng3 etc.
2) Only one IP address is necessary.  You just need to run each masternode on a different port on that IP.