The good thing about working from home is no overheads! Bad thing with still keeping your job and doing this on the side is any potential client will have to work around you. So you may only be able to work nights, and alot of mums may not be able to do it then. Tea, baths, bedtimes, partners working late etc. I work 3 days a week in a salon renting a room. I get the mums in during the day when kids are at school, the professionals in late at night after they finish work, and the full time workers in at weekends when they are off!
Working mobile was a pain for me! It was good to build up my client base as I was flexible and could do anyday at anytime. But the travelling wasnt good, sometimes I would be away for 2hours just to do a spray tan by the time I took into account getting to the clients house and home again.
If you are wanting to commit to this I would rethink keeping your full time job. Can you do it part time?