Depending on the age and condition of the property and the quality of tenants. 

Depends on the owner's age.

When it comes to reserves, I dont use percentages for capex, I use real dollars, based on the age and life expectancy of large items (roof, hvac, water heater, and a buffer for other items).

This means having systems in place as I age so that I am not the only cog in the machine. 

No, with truly self-directed Solo 401k plan you can contribute first $18,500 (plus $6,000 catch up if you are over 50 years of age) up to 100% of your self-employment compensation, then on top of that you can do additional 20% of your net SE income (25% if you are incorporated) for combined maximum of $55,000 ($61,000 for those over 50).

What a small world I didn't think I would find someone on the forums from Adelaide so quickly, especially someone who has made the move over at similar age!  

Being able to adapt to be able to communicate with people of all different backgrounds, ages and personalities is critical. 

I’m 19 years old working part time and am seriously committed to starting real estate investing but being my age how is it possible to invest when I’m only paid $250 every 2 weeks and on top I live with family which will be moving soon?

If the actual vacancy amount ends being lower then I made more money that year.PM averages 10%.Maintenance reserves depend on the age/condition of the property and the quality of tenants.  

I was buying court house steps in fort Meyers  new or near new homes for 30 to 40k cash at the steps in 093. my well documented clients in PHX AZ losing 4 plexs they paid 350k for in 05 and having them go vacant and they let them go to foreclosure thereby ruining their credit and losing whatever cash they had in them.. 2010 they were selling for 100k or less and still vacant.so on and so forth.As long as credit does not freeze the values have been reset .. those that were lucky or smart enough or came of age to be investors and bought in the trough historic low price points historic low interest  many paid cash as financing was still tough.. so as long as they don't drink the cool aid and refi out and leverage up you have the makings of a very strong asset base.. plus all the foreigners who paid cash there were literally hundreds of thousands of homes paid for in cash by Off shore folks.. then add in the half a million or more that were bought by hedge funds..