Just to FULLY support your decision, (as long as I'm thinking of the right boat), that rig should be worth several thousand... Not just $1,200.
I just went back and looked at your rig and your video's... I think that if you were to find a fabric skirt to go where your bildge compartment is, and if you were to rebuild that trailer, you might have a $3,500 boat.
The motor sounds very strong and responsive (not to mention it's the perfect size for that boat). The seats look great, and the finish appears that it couls come back to like new. As is, I wouldn't take less than $2,500 for that rig, and a redone trailer will push it over 3K, no question.
Don't give that boat away! That is a great rig, and the guy that offered you cash new it! He was hoping that you would bite on his low ball offer! I used to own a V-173 with a 85 Johnson, so I know the quality of that rig!
You have a great boat!