Well, you need a PH meter. But if you don't have money for one right now, at the very least you can use narrow range PH test strips. Just be sure they are narrow range--either morewine sells them or E C Kraus.
It's not necessary for you to jump into an SO2 tester unless you want to. However, here's something to think about. If you want to be able to test PH,TA, and SO2 all in one, look at the Vinmetrica SC-200 from morewine. Kind of pricey at $355, but you can get about $80 or so into a PH meter, then if you get the Vinmetrica 100 for SO2 testing, you'd end up close to the price of the Vinmetrica 300. Something to think about, depending on your finances. You could get along just fine, for quite a while, with only buying a PH meter right now.
Your friends think you're nuts to do all this--well, THIS is what today's winemaking is all about. Knowing about providing nitrogen to your ferments thru nutrient management,etc. is something people in ancient times didn't know. And even tho they made lots of wine with native yeasts, we all know that the only time they got GOOD wine was when a tasty native yeast was the most dominate on the grapes. And most of that wine went to the king--not the commoners. So most wine of those times was probably not very good--they just didn't really know how BAD it was because they never had a good wine to make a comparison.
Actually, we didn't work with grapes that needed MLF until we had perfected our winemaking style. But what the heck--LOTS of people do MLF's without tons of experience. It depends on what you're comfy with. Sometimes, trial by fire ain't such a bad way to learn.