87 honda valve seal change

im going to go look at an 87 accord tonight, the guy wants 300 bucks for it, says it drives good, but the one cylinders valve seal is bad and is filing out the plug…

i need something better on gas than my tank of a truck so im probably going to get it… anyone have any expertise on the honda 2.0 engine and could do a fairly accurate write up?

i have access to tools and a shop and will make it a weekend project but i dont have experience with honda engines