What are the best trowels to use? make wise...... i'm told always use a marshalltown trowel, but they're the most expensive of all i've seen, and i cant see what the difference is! is this right? Also i've got a job to do hall stairs and landing and have had a lot of people saying that its too big for a beginner. what is the best way to approach it? do i need someone to help with the mixes or should i just do a bit at a time and use stop beads? any advice greatly appreiciated!!!