i build a portal hut on the shoreline so i can longboat iron out , clear all nearby spawns , put a workbench and chest in the hut with a portal , raise the hut off the ground so you have to jump into it , spawns will happen when you show up , kill them and leave , in that case you can safely leave the boat docked and perform repairs when you show up , or simply put the longboat in the chest for future use ......none of this applies to your first crypt. for the first one i use the karve to get a first crypt , search and search until you find a crypt near the water , the karve is likely to get smashed but you can dock and sprint into the crypt , crypt entry way may have a blob or a draugr or two but is usually pretty safe.
in the crypts you can bow through partially open doorways , spawns make a fly buzzing noise , no point in killing draugr until the buzzy spawn is removed , clubs work but so do bows