I’d expect a seller offering a boat with visible interior water damage other than absolutely minimal is expecting some price negotiating. I agree that it’s priced to perfection at asking price.
If it’s on the hard, it will be more challenging to asses the engine, but it can be done by feeding water into the raw water intake and running it on the hard.
As for rebedding deck fittings, I suspect anyone on this forum has either redone theirs or worries at least a little about it. Can’t me in the latter category. The cost to have it done by a yard might surprisingly high, since even accessing them from below can be a hard to predict for a yard. Most can be got too, but it’s a process.
I’d also suggest getting a good look at the sails. I bought my 1985 32-3 as a bit of a pandemic impulse purchase. Knowing it was not perfect, but also not bad, I consciously overlooked the moldy and heavily repaired mainsail of the which I’ve subsequently replaced with a new one. Badly needed.
Standing rigging is another topic. 15 year old will often be considered due for replacement, but in Puget Sound, if that’s where it’s been, I’d be thrilled to have 15 year old rigging! It’s not that warm or salty here, and it often doesn’t blow that hard either. I believe mine to be original 1985 and it’s high on my list to replace. A question to ask: is there any documentation or records on the rigging replacement. Also good to investigate the condition of the u-bolts that the turnbuckles attach to through the deck. They’ve been known to develop cracks on the underside of the u- bend above decks, according to the forum. Mine seem fine though. But I’d want to replace them when I replace my standing rigging.
Dated electronics likely par for the course. Mine are. They still work, and it’s taught me that gps and autopilot and wind instruments are amenites I’d never go without, and having them offers a chance to figure out what works well and what might be improved upon.
As for price, I don’t think a 15% less than asking offer for any boat is an insult to a seller, and 20% is not crazy either, even for a boat in really good shape unless it’s priced very low. 34k offer would not be outta line here. Maybe even less. Seems like the market for boats, bikes, cars, everything that’s not real estate, has really eased since the pandemic.