i have installed 2 keel guards on different boats. it takes some time, but it isn't that hard. i used an orbital sander with 200 grit paper (i believe) to do my prep work. before you sand, TAPE the guard in place as best you can and mark the edges so you know where to sand. sand thoroughly so that the whole gel coat is dull looking. then get 2 CLEAN towels and clean the whole area with solvent. there are several recommendations on the directions and all are available at the hardware store. after you clean it 2 times each with a clean rag, you can apply the primer. shake it very well and apply. it doesn't go on thick, but you can see where you apply it fairly easily. now for the tricky part....remove about a foot of the CENTER piece of tape and center it on the hull as close to the saftey strap ring as possible. take you time and make sure it is centered and it will be easier down the line. if you mess up, it is EXTREMELY hard to back up and start over. DON'T ATTEMPT TO INSTALL IT UNLESS IT IS WARM OUTSIDE!!!!!!!!!!! if it is cold, you will NEVER get it on correctly. i think the pkg. recommends 50 degrees plus. i would recommend higher than that. the warmer it is, the easier the installation! i would DEFINITELY wait until summer unless i had a heated garage that i could heat to over 70 degrees or more.
if you have anymore questions, let me know or drop me an email. you can definitely do it yourself and save the $$$.
bryan