Be aware, this hotel is not situated in Portovenere, but Le Grazie. This is a 10 minutes busride from Portovenere.
We stayed 2 nights during our honeymoon. After having dinner, we arrived at the hotel at midnight, and the main door was closed, and nobody opened. Luckily we had the tlfno. to the hotel and got contact with the nightportier after 30 minutes.. Very bad experience.. No excuse the day after when we informed the staff at the front desk.

And the hotel need renovation.
Stay away from this hotel.

Having visited this nice little town 20 yrs. ago, I dragged my wife back there in 2005 and stayed at this hotel for 2 nights. We loved it so much we used it as our base of operations for a week in 2008. We requested and got a bay-view room, and the view is fabulous. The hotel's Cul de Sac is very quiet -- very rare in Italy. The rooms are above average, clean, and the breakfast good, considering the reasonable price.
We made daylong driving & boats trips to all of the Cinque Terra towns, and also drove to Pisa. While we did eat a great anniversary dinner in close-by, touristy, pretty, Portovenere, but we found ourselves walking from the hotel along the waterfront of the small Le Grazie harbor most nights. Locals come out to walk & talk, and there are very few tourists. Folks are friendly, and we felt like we were welcomed visitors in a small local community. We got this feeling no where else on the trip. We had the best pizza on our entire month-long Italy trip (a corner place with a brick oven about 4 blocks from the hotel), and one night a large sailboat left the harbor with great fanfare, and a family party which we were invited to -- (we speak no Italian, it never seemed to matter). Le Grazie has no clubs, no fancy restaurants, and one nice church. It is a throw-back, a hidden treasure, if you can slow down enough to enjoy it....

My husband left me in charge of booking our hotel for a 4 night stay in the Cinque Terre region. He had picked out a hotel called Hotel Baia in Monterosso, the northernmost village of Cinque Terre. I got confused and booked us at the Hotel della Baia in Le Grazie (their address says Portovenere, which is doubly confusing and mostly inaccurate). Having never been to Cinque Terre and having not looked closely at the map when I was booking, I was oblivious to my error until we got close to it by car and he realized I was giving him directions to someplace he had not planned on going!
We stayed 1 night at Hotel della Baia in Le Grazie and they were very kind and understanding about the error and let us out of the other 3 days of the reservation. We called Hotel Baia and booked there for the next 3 days (see separate review on that one).
In the end, if you WANT to be in Le Grazie, Hotel della Baia is a very nice place. It's a tiny bay, we were there on a Sunday so it was quiet. The hotel is quite nice. Our double room with breakfast was 75 euros. The room was reasonably spacious, clean, quiet, with a tiny balcony overlooking Le Grazie bay - very very pretty. No complaints (except from my husband who thought we'd be hiking the Cinque Terre trails the next day!!! - ooops.)

In theory it ticks all the boxes but there is no atmosphere and the staff are 'just doing their job' - we just didn't feel welcome. The room was airconditioned and had a nice view - but was as small as they could get away with. Dinner was dull and all they had for vegetarians was omelette or a salad (a tomato and a few slices of cheese). The pool was OK but freezing cold on even hot days, plastic loungers and no service - few guests used it.

My car was hit twice while parked outside and Le Grazie itself is a bit scruffy - not a resort and only a few restaurants. It's really where sailing enthusiasts go for maintenance or supplies.

So all in all it's OK but not somewhere I would make any effort to go again and expensive for what it is. It would suit people who enjoy sailing or a very quiet holiday but there's nowhere to sit and relax!. Easy to get to Cinque Terre though and La Spezia and good public transport..