Exchange wouldn't be the right word. Perhaps,

For sale, [big boat], asking $$$$$.$$, will consider taking [small
boat] in trade.


Ok - 2 things could it then be:

Sailboat 45f - asking 250000$
Consider trading with - [small boat]

and the menu for reaching the page could be:

- Consider trading

or does that make "no sense" ?

regards
per