could u get away with 2600 psi
ask yourself these questions,
A)do you want to do the job quickly and effortlessly with outstanding results?
or.....
B)do you want to save money on the one thing that makes you money?
if your answer is A then the answer to your question is no.
if your answer is B then the answer to you question is, you can get away with any psi, just don't expect too much repeat or reccomendation work.
buy the best you can afford. it will be your bread and butter.
hope this helps