I think cost is very important but should definitely not be the only criteria. I put together a small comparison based on 4 different amounts: $10,000 - 25,000 - 100,000 - 250,000
Yearly cost at different portfolio values:
StashAway: be careful, they do stacked pricing, means you pay 0.8% for the first 25,000, 0.7% for the next 25,000 etc so if you total is 100,000, you will NOT pay 0.5%, but 0.68%
AutoWealth: charges a fixed $18 per year + 0.5%
Syfe: 0.65% below 20,000, 0.5% until 100,000, and 0.4% above 100,000; their pricing is tiered, meaning if your total is 100,000 you will pay 0.5%
Anything I missed? Looks like Syfe is the cheapest based on the 4 examples I picked.