this has probably been said but, with suited cards you want something with connective value, k 2 its probably stretching that q 8 suited is a possible call depending on your table image and the level of skill of your opponants... personally i would call with one or two gappers that are suited on the button, as long as the blinds arnt likely to raise you out of the pot..
definately dont raise with these hands, its defeating the purpose of playing such cards. you want to get in cheap, with multiway action against loose bad opponants who are likely to make big mistakes postflop.
oh but the latter part of your question, if you did, want to make a dead money grab there.. basically you would need to look at the pot size, if the pot is say 2000 you will need to make it around 3-3.5k. or even more if you are out of position. with this play your main aim is to steal the money which is out there already and not put a cent more in, so really your hand doesnt matter.
say the blinds are 50 100, there are 3 limper in front of you, (the first limper is most important, if he is likely to call i would cancel this play) so actions to you, you get dealt 7 2 offsuit.yay. you feel the first limpers weak and the ohters will fold to action. so you decide to make a dead money grab to take whats out there hopefully without a fight.
there is currently 450 out there so making it to around 900-1000 would seem to be enough. basically around double the size of the pot, more if you are out of position. again, if you happen to be called thats the end of the hand for you, i wouldnt advise continuing with the hand unless you flop good. and its also a play which you wouldnt want to risk more than 10% of your stack with.
its a good play when the tables limping a lot and will fold to pressure, but i would use it very sporadically as it is high risk, but with a high success rate.