Thru-hulls and seacocks are easy and pretty hard to screw up. I installed 4 new thru-hulls/seacocks on my power boat recently (one 1.5", two 1" and one 3/4"). My total cost was under $350. It probably took me about four hours total, but I moved two of the thru-hulls and that time included patching the old holes. I used groco seacocks and conbraco thru-hulls (without nut). They are all bedded in 3M 4200. It is a generally easy job. Of course, I tend to take on what some people might consider fairly major jobs on my boats. Face it, boat work is not exactly difficult. Anyone can do it