A suggestions for setting up a wireless security camera with a Mac?

I just moved into a new place. There are two dynamics that are encouraging me to set up a wireless security system.

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1. Large front windows that showcase quite a bit of expensive musical equipment and flat screens.

2. It’s impossible to see who’s at the front door before coming downstairs to answer.

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Any tips for an affordable solution that I can hook up to my Mac to monitor? Thanks!