Hello Bob,
There is another thread on the forum why are there no ETF savings plans in Switzerland?. In summary Switzerland probably lags behind some other countries in respect of such offerings.
Of course she could ask a bank like UBS or CS.
Assuming she does not want to do this then here are 2 ideas:
(1) Pay a service provider like Truewealth or Selma. There are reviews of their services online.
They charge in the region of ~0.50% of assets. In your sister’s case perhaps this a fair fee for a service received
(2) Interactive brokers recently enabled recurring investments - on USD assets at least - and auto currency conversion. This will almost certainly be the most cost efficient option
I am not sure if it is possible for CHF ETFs but after initial set up she should be able to transfer CHF each month and buy the US listed version of VT
In settings she can set her account default currency as CHF so all her reports show in CHF - which helps for swiss tax return etc.
However set up in Interactive Brokers requires some patience. I would say this is only an option if she is prepared to do some work or perhaps if someone can help her.
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Above all: she should be wary about the self proclaimed “financial advisors” who cold call UK expats and offer “tailored solutions”. They usually peddle products involving attractive sales commissions