you can start with a used porty(we did 1500$) some tools(500$), so for like 2k and some chems your good to go.
But keep in mind a porty is slow, heavy, always needs refilling & very loud.
We used a porty for 5 years, got to a point where I started to hate going to work because the porty was sooooo much work. Even a small job(like 3 rooms and a hall) will take 3 hours!
With a TM that job would take half the time.
We put down like 4k and our tm cost about 380(including 50 bucks insurance) a month and I enjoy my biz again.
There will come a point when you have clients and cant do them all because the porty takes to long(and is too much work). I would still get the porty, but as soon as you can get a TM.
Also make sure to take some classes(
cct).