In this order I would look for

At least part of the land above a flood plain level
Good Soil and water
Existing Perma-culture, wild and tamed
Garden Plot
Small animals chickens, rabbits (can be left alone for days)
Medium animals mini-goat milkable. Ties you down!
I would only get a milking animal if I had a partner or
extremely trusted neighbor.

Naturally Small cattle -- general purpose.
An alternative to a draft horse or mule is an ox (steer).

BTW, you could have a couple chickens on a 20ft boat.
I saw 2 chickens on a ship in the movie Captain and Commander.
You could feed them fish guts and let them graze on shore.