I'm not familiar with the wellcraft 192, but the 4.3/Alpha is a good, dependable package (asuming it's been well cared for)
Anti fouling is no big deal, and would cost you a couple of hundred quid.
Has the boat been wet berthed? (kept in the water) if so, it's worth making sure the Alpha drive isn't too corroded.
If you're not mechanically minded yourself, I'd reccomend getting it surveyed, at least the engine/drive, if not the hull as well.
"I Agree with everything you say really!" - John Cooke to Jon Fuller - 26-01-2013