Adrian, we have stored the trailer upright in the past with no problems. You did not mention what size the trailer is and we did it with a small (hauls 14 foot) trailer and had no problems.Be careful raising it up against the house so the the box frame of the trailer does not dig into pavement (use some boards as pad to prevent this) you will have to secure it so it won't fall over or lean it back for a good safe angle.Of course you will have to protect the house sideing as well.We did this in a barn and used a block and tackle to raise it up but use caution(it is heavier then you think)if you are trying to manhandle it up against the side of the house.All in all not sure it is worth all the effort. Won't the marina let you keep your trailer there when the boat is in the water? If not you might want to consider a storage yard or some other area. Can you put it in a back corner of your yard? Your post said you have a 19' so the trailer is (I'm gussing) 24' overall,that is very tall when you think about going on the side of a home.Might want to rethink this one. Good Luck !