I would go against that advice on goggles and airI reckon you will be best off by getting a good goggle eg. i4 or maybe a proto axis if budget then spending the next on a solid air supply that can last your whole career, then spend the rest on a second hand gun from here; some really great deals i have seen!
Goggles yes - spend well, but try on many pairs. You need comfort, face & ear cover and visibility. There are very good reasonably priced goggles, if you can afford i4s it does not mean they are best for you or that the 'enhancements' of premium goggles are worth the extra £ to you
For air rather than 'lasting your career' any air cylinder will do that, in fact steel/aluminium cylinders could last your lifetime - keep it in good condition and keep testing it
Fibre cylinders have their benefits, but these are realy worth it when in the right configuration of length, capacity, position.
The old argument was that it was a waste of money for a new player to buy budget goggles & a 3000psi cylinder only to want premium goggles and a 4500 cylinder later. Better to 'waste' a little with a small second hand value then not being able to afford to play next week. Let alone spend hundreds then get bored after a month
Either way the typical paintballer still wants to buy shiney new things as soon as they have extra cash in their pocket. No matter what you buy you soon find yourself 'upgrading' to the next one