How much can you raise the rent at one time

[Julie Macd]

Hi everyone, This is officially my first post on Bigger Pockets though I have been following all the site quietly for a few weeks.

I own a SFH which has had the same tenant since May 2011. When he moved in, the rent was at market, maybe on the low side, though I have not raised rents. Since this time, rents in the neighbourhood have gone through the roof and from my initial market research, if I was renting today, I could probably get an extra $500 per month which a 25% increase. If I raise the rent too much, I will have to hire a property manager to find a new tenant and manage as I am overseas.

He is a good tenant, takes good care of the place and pays his rent on time. So what is a reasonable amount to raise the rent in such a case, so I can increase my cash flow, but not lose the tenant.

You advice is greatly appreciated.