Puerto Natales to Chiloe

Hello there

A friend and I will be travelling from Puerto Natales to Chiloe between Christmas and New Year. We'd like to do it by boat but the cost of Navimag makes that an impossible option (we are poorly paid English teachers). Does anyone know:

1) of any alternative boat companies?

2) how long is this option likely to take?

3) is it possible to do part by bus and part by boat?

4) how 'joined-up' are the services?

A lot to ask, I know, but here's hoping...

1) no alternative boats
3) yes, a short, cheap and amazing flight, seeing the breathtaking Ice Field South (Sky airline) P. Arenas-Balmaceda (airport of Coyhaique) and there a ferry (more cheap) to Quellon or Puerto Montt. Also there was a bus (Bus Sur) connecting Punta Arenas-Coyhaique, is stopped now but ask for a future re-opening to www.bus-sur.cl