It sounds like you need reliable transportation on the cheap, AKA "a Daily". I'm sorry to say that I don't think the Z is going to be that at all. Getting the blown gasket fixed might fall just inside your budget, but you'll have nothing left over for all the other stuff that's wrong with the car (yes, there is other stuff besides the head gasket that will need love ASAP). Plus you have reg, tax, insurance and maybe an inspection to pay for. You ever see BMW's parked in apartment complex's with bald tires and a headlight out or expired tags? They can't even afford to keep safe tread on the car and can barely keep it full of gas, let alone falling behind on payments or insurance coverage. Don't just have the car, be able to afford driving and enjoying the car.
Welcome to NICO!
Look around here a while and do some more research. I don't know you and your capabilities. The old Z's are sexy cars and I can fully understand wanting one. Some people can make things work where others can't. We often help with reviewing an ad for a car if you'd like. There's a lot of threads here. I did some search with key words like 300zx or Z32 together with reliable or maintenance and think you might want to also.
Some threads to see:
z32-project-car-help-with-purchase-t618776.html
post6728656.html?hilit=300zx%20reliable#p6728656
post6736926.html?hilit=300zx%20reliable#p6736926
post6741544.html?hilit=300zx%20reliable#p6741544
craigslist-find-of-the-week-t527194.html
I'm going to move this to general discussion since your not actually doing a repair but are speculating a purchase.