What do you think is a reasonable rate of return?
A reasonable rate really breaks down into three things: opportunity cost, what you need, and risk appetite.
Opportunity cost comes into play because whatever returns you make should at least exceed, after expenses, the next best option. Typically the "next best option" is the risk free return you can get somewhere else, which is typically a savings account or some other (safe) investment vehicle (e.g. a guaranteed investment certificate/GIC, bonds, etc). But, this opportunity cost could also be an alternative investment (e.g. an index ETF), which is not necessarily risk free (but it may represent the next best option).
Risk appetite comes down to the amount of risk you are willing to take on any investment, and is completely subjective. This is typically "how much can you sleep with losing" amount.
What you need is the most subjective element. All things being equal (e.g. identical risk profiles, access to same next-best-thing to invest in), if your cost of living expenses are only expected to go up 2% per year, but mine are expected to go up 3% per year, then my reasonable rate of return must exceed 3%, but yours must only exceed 2%.
That said, an appropriate return is whatever works for you, period. Nobody can tell you otherwise.
For your own investing, what you can do is measure yourself against a benchmark. E.g. if your benchmark is the S&P 500, then the S&P 500 SPDR ETF is your opportunity cost (e.g. what you would have made if you didn't do your own investing). In that way, you are guaranteed the market return (caveat: the market return is not guaranteed to be positive).
As an aside..
Don't ever, ever, ever let someone else handle your money, unless you want somebody else have your money.
There is nothing wrong with letting someone else handle your money, provided you can live with the triple constraint above. Investing takes time and effort, and time and effort equals opportunity. If you can do something better with the time and effort you would spend to do your own investing, then by all means, do it. Think about it: if you have to spend 1 day a month managing your own investments, but that day costs you $100 in foregone income (e.g. you are a sole proprietor, so every day is a working day), that is $1,200 per year. But if you can find an investment advisor who will manage your books for you, and costs you only $500 per year, what is the better investment? If you do it yourself, you are losing $1,200. If you pay someone, you are losing $500. Clearly, it is cheaper to outsource.
Despite what everyone says, not everyone can be an investor. Not everyone wants to live with the psychological, emotional, and mental effort of looking up stocks, buying them, and then second guessing themselves; they are more than happy to pay someone to do that (which also lets them point the finger at that person later, if things go sideways).