Was doing a vSphere Optimization Assessment (VOA) and wanted to advise customer on the resources required. Other than the documentation from here or from the vR Ops Installation Guide, it does not state what was provided e.g. the different profile sizes of the vApp is suited for which type of environment other than running the deployment wizard. This is not very helpful especially when you are doing planning and the only way to get that information is to deploy it.
Upon deploying, you will get to know the disk size that vR Ops will use. Based on documentation, was 250GB however in the wizard it shows 1.4GB for thin provisioned and 266GB for thick provisioned.
Running out of Disk Space?
What if you run out of space for your vR Ops vApp? The procedures of increasing the disk size is stated here. It is fairly easy by just shutting down the vApp and expanding the vDisk 2 or adding a new vDisk and powering up and everything will be automatically detected. That definitely make life easier without having to bother to configure later.
Some environment require vR Ops to be placed in another network no similar to vCenter. This would require the need of opening some firewall ports which are all listed here.
Update 15th Jul 2015
Apparently there is a sizing guide in this KB but not updated as of 6.0.1.