There are so many unit trusts out there, which ones do I pick? I have a time horizon of about 5-10 years!?

You do not have to select if you are concerned. Just head to any roboadviser and start your RSP based on your risk profile and time horizon.

Lump sum has better statistical returns, but they are hard to adhere too. DCA is often a strategy used because of its high adherence rate.

Some insurers like Prudential work with Mercer to remove selection bias.

There are many solutions above to solve your problem, the days of needing to select your own funds is not really a problem today from the above platforms mentioned.

Always start with asset allocation and your risk strategy.

Then decide on the exposure into geographies and industries.

And lastly the funds that give you that.

For a 10 year goal, I may just use a 60/40 Equity Bond split and have 30% US, 15% Asia, 10% Europe, 5% Emerging market for the equity exposure.

And 20% Immediate Term High Quality Bond, 10% Long Term Corporate bond, 10% High yield corporate bond for the fixed income exposure.

Lastly, just DCA whatever you're comfortable with now and start an RSP on top immediately.​​​