I think £160 a day isn't too bad, If I'm quoting for decorating work, I'd need to come in at a little less than that, if I'm fitting a kitchen, it'll be more than that.
I hate doing small jobs and rarely do unless it's a regular customer who I'll always try and help out.
I've ignored 4 messages this week, one was 'can you give me a quote to fit worktops in my new kitchen'. I didn't call back because I would have likely been rude to them. Who fitted the kitchen? get them to quote.
With a handyman type business you're going to be fannying about doing small jobs, even to hang a few pairs of blinds it's probably 3 trips to the van bringing in tools then 3 trips back out, 4 if you forget the radio. With small jobs, you'll never achieve £20 per hour because of setting up tools, travelling etc etc, there needs to be a minimum charge (maybe 45-50 for the first hour) and then £20 per hour thereafter. £160 a day is OK but too many small jobs could see you at £80 per day.
Also, your area, lots of retired people, a lot of wealth. Don't put out a pricelist as such, keep it flexible. £20 per hour is fine but if somebody from Sandbanks or Canford Cliffs phones up, stick another £5 per hour on at least, an extra £10 per hour if it's Harry Redknapp.
Other than that, go for it, it's a challenge, it can be rewarding, no two days are ever the same and if nothing else, you'll meet some very interesting people.