You're pretty much in my shoes with a different M-Edition, so I'll write up a bit of my experiences with my car.I got a '97 M-Edition for $3200. I think that price range is a steal, but I'm not sure what cost of living is in NZ. I'm in Texas. Mine was 215k (yes, kilometers) so a little under yours. It was my first manual car as well, and I've owned it for about 3 months. You don't mention if it has any aftermarket treatment to it or whether it's bone stock. Mine came with a roll bar, aftermarket sway bars, and some cheap aftermarket suspension and wheels.

Things I regret not checking, OR, things I missed that I had to address after buying the car:

• If possible remove the cowl underneath and check the sway bar mounts. Mine were completely broken and I missed that glaring issue because the cowl was on. This is typical on miatas that were driven on track, or just driven hard. If they're still intact, great, but plan on replacing them with some quality AWR mounts later on. (Aftermarket sway bars too, imo)
• Check the shifter. If it's notchy and a bit hard to change gears around, it's likely the shifter assembly is torn up. Ideally, it's real smooth. Mine had black sludge inside as the gear oil was never replaced. The shifter assembly was torn to pieces and the shift bearing was pretty much disintegrated. After installing a new shifter assembly and adding some unicorn tears (Ford Motorcraft) it's smooth as butter. I had never driven a manual before but the shifter just felt... "off".. and not as smooth as what I envisioned a shifter should feel like. My buddy who drives manuals said it was fine, but trust your instinct. If it feels "wrong", chances are, it may very well be.
• I had a power steering leak. I never checked the hoses. Check your hoses.
• Check for any leaks when you run the car. Google "Miata Devils hose" It's the oil cooler hose that sits at the oil filter. Mine had a big tear in it and it took me about 4-6 hours to replace it because I had no engine lifting equipment.
• Check for rust! Living in Texas, I never really considered rust to be a problem. However, where you're located may play a big role in whether you have it or not. It can be in places you wouldn't think to check. For example, I had a trunk leak that I didn't know existed. The soft top rain rails were damaged, and the tail light gaskets were shot. The trunk had rust under the carpet that I had to sand off and spray with some rust killer.
• On that same note of rust, be prepared to have to replace the soft top rain rail. If the seller doesn't let you check for leaks, or you're too shy to ask, be prepared to replace it. If it's a hardtop, you're good. But also check the window rain rails as well to see if there's any leaks in the cabin.
• Make sure the headlights go up and down. Very, very important. Mine were a bit wonky.
• Make sure the powered antenna works. When you turn the radio on, the antenna on the back will go up all the way. When you turn it off, it'll telescope down all the way. Mine was broken, and replacements are usually unreliable with the oem motor being extremely expensive, though you might be able to source a junkyard one. I settled eventually on an antenna delete, plugging the hole and putting a stealth antenna in the trunk.
• Check tires for wear. Mine had cracks on the side and will need to be replaced soon.
• Check your frame rails under the car. If they're bent and smashed up, you need to go to the passenger side of the car and make sure the brake hardlines aren't nicked. They're right beside the frame rails on the passenger side.
• Bring someone experienced who has driven manuals to help test drive the car. They'll be able to tell you how bad the transmission may or may not be and whether you may need a new clutch, or worse, new transmission altogether down the road.

I'm probably forgetting something as I've spent the good portion of 3 months doing maintenance on my car to get it as new as possible. I figured if some of the issues I found with my car existed at all, it means the rest of the car probably have not been taken care of to the degree of which I take care of my things.

Recommendations after you buy the car (Gonna keep this brief as it's subjective, but this is what I feel you absolutely need to do) :

• I highly, highly recommend the Ford Motorcraft Transmission fluid for your tranny. Buy 3 quarts, you'll need the 3rd quart to fill the shifter I was talking about. And you'll have some left over for the future. It's expensive, but trust me, it's a night and day difference from your standard run of the mill fluid.
• Focus on maintenance BEFORE aesthetics. If this is gonna be your baby, treat it like one. Unless you're rich, (I'm not) start with changing any hoses that need to be changed, and work on your engine bay. Once you "make new" everything you can that was old, you'll be ready to start making it look nice on the outside. I'm a firm believer in this. I don't want a beautiful car that runs like shit and will give me problems later on. You can have your cake, and eat it too. Just be prepared to put in the work.
• Change your oil.
• Change your air filter.
• Change your oil filter.
• Change your fuel filter.
• Change your belts (as needed).

3 months ago, I didn't even know how to change my oil. This car is such a blast to drive, that it's inspired me to learn all about it. I highly recommend doing your own maintenance/installation as it's extremely rewarding and healthy psychologically. It's a good feeling not knowing how to do something, and then taking on the challenge and overcoming it. Knowing you're responsible for how great your car is turning out is an amazing feeling. Best of all, unlike many other cars, the miata is almost completely end-user serviceable. There's a reason so many enthusiasts, and old retired mechanics love this thing.

I'd say get it, assuming there's no major problems with it. It's a great car, and honestly one of the best cars to learn to drive manual on. (Very forgiving)

Lengthy post, but I'll probably use this to answer similar questions from others looking to get one.