1. Monitoring; if you lost a significant number of sales, it was mostly because you didn't know your site was down. Solution: nagios running on a pc in your of

1. Monitoring; if you lost a significant number of sales, it was mostly because you didn't know your site was down. Solution: nagios running on a pc in your office. Or use one of the many external monitoring tools that will send you a page if your site is unavailable for more than 90 seconds. 2. Separation of concerns, the server that handles credit card transactions should be a different machine than the one that delivers static media. Databases shouldn't depend on webservers and vice versa. 3. Load balancers don't need to be fancy, you can distribute high impact loads across multiple backend servers using nothing but free software. 4. Eliminating single points of failure is a good idea, but it gets expensive quickly. Try to identify which bottlenecks are actually giving you grief before you charge into building complete multi-tier architectures. All that aside, if $50 bucks is the limit of your hosting budget you are in trouble. To run a relatively high traffic site you should have at minimum separate web and database servers, and your database server should be on dedicated hardware.