I have 10 years' experience as an owner and would warn her to be careful that she does not become tainted by time wasters.

Good customers warm to enthusiastic designers and can be put off by even the slightest hint of doubt or suspicion.

Time wasters are an unfortunate but inevitable part of the process. 

Some of them are design hunting, some of them are window shopping and some are good leads that you lose to a competitor, although no retailer will admit this.Some time wasters don't even realise that they are going to fall into this category, this is the fault of the retailer for not conditioning them at the outset.

A good qualification process will eliminate some time wasters, but the only way to guarantee no time wasters is to present no designs at all.