Take a look and see if you can find a Sekonic 408. It's a 5 degree spot, so not the most refined measuring tool, but it will do ambient and reflected and spot natural and strobe readings, and is highly accurate. It's also weatherproof (don't go swimming with it, but if it gets a bit of rain/mist/humidity around it, it won't go up in a blaze of electronic smoke either). There's one for sale on feePay right now with 2 days left and it's at $100. Someone (I think one of the internet scam(or should I say scum) artists) has one new in box for $319. I'd guess you could pick one up pre-owned for somewhere in the $200 or less territory. I've had mine for over ten years now and been quite happy with it.