While you could consider this aparthotel option for your first time in Saint Petersburg, it's particularly suitable if you are already familiar and comfortable with the city. New visitors might feel more comfortable at one of the 4-star hotels.
Boutique Apartments Classic consists of some number of apartments in an ordinary modern apartment building that are rented out to guests. The apartments are nice and well equipped. Mine had electric stove, oven, microwave, fridge, coffee maker, kettle, dishwasher and clothes washer -- all modern and new appliances. I think all the apartments have balconies and mine had a nice view. The WiFi is good and there is TV but all the channels are in Russian, so you might not have anything to watch unless you speak the language.
You should know that they will want a 10,000 RUB deposit in cash, refunded at the end of your stay minus payment for the minibar or the cost of anything destroyed. That's reasonable, but I mention it so that you can arrive prepared.
The location was good for me. Not the center of town, but the red line from the Baltiskaya metro station gets you there pronto. On the way to the subway is a super-convenient and huge 24 hour Lenta supermarket. Makes it easy to stock the fridge (including beer and wine) and features several ATMs.
Boutique Apartments Classic is a perfectly good aparthotel business to deal with if you want to save money, don't need hotel services, and might like to live with the locals. I enjoyed it!