I am little curious if there is any possibility to make floating train/caravan with ~3 houseboats. Theoretically this is possible in TS3 without any mods- you need to buy 3 houseboats, park them closely together and then order captains to sail into the same spot, but you need to have luck that they will choose the same path, same speed and no crash to desktop. I am sad that Maxis didn't allow us to make longer boats, so they could look like real big ships, so I am looking for alternatives.

Don't get me wrong- I am not looking for someone who will do it for me, but rather how I can start making this mod and if modding tools even allow for this.

I haven't looked, but imagine you can make a houseboat larger, by cloning with TSRW, or maybe s3oc. Next comes the routing issues.