edited to say: ooops edited to say, i didnt read correctly - you already have $30 k savings. Well, I still think save another $10 k before investing.
I'm following this thread with interest! I'm in a similar position to you and earn the same amount of money, although i'm around 15 years older than you & plan to fully retire when I hit 60.
Anyhow well done on starting your investing so early! You have less pressure as you have 25 years till when you want to retire. If i were you imo I'd wait some time and build your cash buffer some more as you are already quite NG for someone on your salary. Maybe save another $7 - $10 k first, then the next one you buy make sure you get a loan that covers every cost including stamps, settlement, building reports, pest inspections (absolutely everything) so that you dont have to fork out anything from your pocket. You will also need to budget for things like accountant fees etc.
See thing is what happens if all of a sudden you have to replace a roof on your ip, and 1 of your ips becomes untenanted, you were to lose your job, other unexpected property expenses or non property (life expenses come up like having to buy another car, repair a car, buy a new washing machine, medical bill etc) Make sure you have landlord insurance, income protection insurance etc. I agree with you wait till you have at least $25 k or even $30 k in the bank and then be careful in what you buy so its not too NG. Also by the time you have saved the $30 k in your bank your rents would have gone up and your 2 ips will be closer to neutral.
My ip is close to neutral and I had $35 k in my bank and was all set to buy ip number 2 but then my car died and I bought a 2 year old sportswagon for $18 k. My plans have changed a bit now as I only have $15 k atm. I'm trying to decide now whether to invest when i have $20 k in the bank or wait till I have $25 k in my bank. Its a fine line. If I wait till I have $25 k it will be another 9 months before I can invest though. I'm visiting my accountant to work some cashflow examples to see what the best type of property for me to buy is, to see just how out of pocket the property type will be. Then I'll know what propertys to visit when i go to home opens.
I want to be reasonably aggressive with my investing yet conservative too in that I dont want to be forced to have to sell out and I want a reasonable balance in life too in that I dont want to have sacrifice crazily so that I dont enjoy my life in the interim.
Good luck with it all and I hope you continue to post here as I'd like to see how your experience unfolds. I agree that next time you should go for something that has value add potential but make sure it is not too NG that you struggle with the cashflow. Also listen to your gut make. Something is telling you its important to wait till you've saved some more, so do it. Sometimes its best to do no investing at all.