Use this site to build a view of your property portfolio from your spreadsheet data. It can display thousands of lines:

To try out, just click the DataView button above and download and modify a sample file (important! - use the same column headings). Then upload it to create your own view with your own data. When your view is displayed, click any window to see your tenant details.
(1. quick start 2mins) (2. map your own data 8mins)

(The view below is from a spreadsheet listing dates when rent was last revised. Rents revised over 12m ago are highlighted red)