Personaly I don't think tipping on the massage is neccessary irregardless of length.I don't tip my chiro,accupuncturist or my dentist either.20 should be sufficeint for your basic yank.If your roaming all over and sometimes under,go accordingly,30 would be alright .40 and some things gotta go.Beyond that,possibly a bit more complicated.Your average mp,if she does these options,normally expect to dish out 60-80 for birthday gear.from there its pretty much a crap shoot as to what else is available and what will be the required contribution if any.this is where the intangables come in to play.no 2 situations alike.some times someone may have more bargaining power than others and viceversa.