Hi mate yes you can i started a 3 months ago,started from scratch coming up to 60 custys .
Im picking up about 20 per month.You can claim for the hours you work even if you are not earning in those hours eg posting flyers ,door knocking etc .I claim 30 hours per week ,tax credit works on the years earning in the previous year ,as i earned over 20k the year before you can get them to do there calcalation on this years earnings so you will need an estimate of what you will earn hope this helps