Painting over oil based exterior wood finish

[Edufixer]

Not sure how to repaint an inherited summer house. The exterior is reasonable sound but has been painted with an old oil based paint. I have repaired rotten shiplap, filled and sand exterior to provide a key. What is the best paint to use to repaint the entire exterior, it is not possible to take it back to bare wood?
Thanks

 

[opps]

Why not just use another oil based paint? Eg. Dulux Trade Weathershield

 

[sparkwright]

Water-based Sadolin Superdec, which comes in a small range of solid colours, is a quick drying paint which resists cracking and flaking, and sticks well to properly sanded old oil-based paint.

 

[Edufixer]

Thanks will do