For PLA I use a glass bed and a glue stick. No heating pad. Perfect everytime if bed is level. 400x400 bed.
Best stick brand I've found is Pritt - the glue does not build up as fast as many other brands. I buy the big sticks.
Rub evenly and you can wipe with your finger as well, if there is build up or skipped section. Perfect is not required. Wait 3 minutes before initiating print. PLA melts it a little as it is extruded and sticks. If bed not levelled - PLA will not stick.
I clean bed off once a week when buildup gets too high (blobbly). No need to super clean after each print.
I crudely scrape buildup off with putty knife before each print and reapply Stick over old glue.
I have managed two months of daily printing without cleaning the glass completely.
Washes off in water when you need a complete clean.
If you want a really nice flat base then clean and apply glue on clean glass to get nice surface.
I don't recommend hairspary because the overspray builds up. Glue stick can be applied in-situ.
In the past, for me, the best surface - if not glass - is Polycarbonate. A 3mm sheet clipped onto the bed.
PLA will stick direct without glue but glue is still better as success rate tends to 100%. Do not confuse Polycarbonate with Acrylic. Entirely different plastics.
I don't do much ABS - theoretically you need heated bed for ABS but I use glue. A perforated board is ideal but as object size increases the cooling is less even and shrinkage will deform it. ABS juice (link below) seems like the right thing to me but my experience is limited.
My bed is 400mmx400mm. I can print small or massive and always sticks. I use PLA all the time - less toxic and my printer is indoors. To smooth it, I either use a heat gun, fill with plastic wood putty from h/w store and sand, or use Smooth-on XTC which is pretty nice product, spreads well, shiny surface, smoothes out ridges, can be sanded, reworked, overpainted.
I agree with pretty much everything this guy says and he has some ABS advice which seems sound to me: