Moving into a new home where the dining room and living room had been
sanded and finished by the sellers.

Problem is, there are some large gaps inbetween some of the planks on
the floors that are refinished. Now I know of the tricks to fill these
using a mixture of sawdust and glue (or varnish) but don't have any
sawdust. What are some other alternatives?

Would I need to varnish the floor again after repairing the gaps?

Also, we are probably going to have the remainder of the floors
refinished, should I wait and try and get some sawdust from that? The
floors are under years of paint as well. Would that be a problem, or do
i just wait until the paint is fully removed and take the dust then?

1st time homeowner (just closed yesterday!) so any advice would be
greatly appreciated.

Thanks
-Owen