You know, I've been reading and trying to keep my 2 cents out, but I feel the need to point something out. I'm not sure where the fault lies in this one, and it very well may be shared, but something has been bugging me. If you advertise a professional service and charge accordingly, you best have the knowledge, tools, and ability to do a professional job that is worth paying for. If you fall short in any of those categories, you should very well expect to be issuing refunds and buying back saws or whatever it is that you did less than a top job to.
Now if this doesn't apply here, I extend my heartfelt apologies. But let this be a cheap lesson to newcommers to the game. We all started somewhere, and not a single one of us came out of the womb knowing how to massage a cylinder just so. However, it would be good advice to heed that you start on your own personal and cheap saws and aquire the neccessary bare essentials to do the job right before you jump into business doing just that. Either way, it is unwise to start charging for something that you are not both confident and proficient at.