I am and have been a manger and investment property seller for the better part of my life. If i wasn't managing them I was selling them if i wasn't selling them i was remodeling and building them.

a couple of things i like have been mentioned,

location location location,,, the better location will attract a better quality of tenant and save you on repairs, itwill be easier to sell for reasonable market value in the end.
buying a low cost rental in a crappy neighborhood will attract that type of tenant,

the investment dollars and LTV ratios don't really mean anything to you if you really plan to pay it off before turning into a rental. you will have no debt service and will cash flow immediately anyway.
if you are using it as your primary residence when you move in you can purchase the home with FHA or other govt backed loan, you initial investment can be done with a lower downpayment. If you plan to use it as your primary residence, what you do down the road is not their concern.

remember that you will lose your capital gains tax shelter after renting for three years, so if you do have a large capital gain (market comes back strong) you will be subject to taxes unless you move back in

stay away from renting any type of common owner situation (condos or townhomes) where an HOA is in charge of common area maintenance. even if you own it free and clear the HOA fees and any potential large repair could cost you everything you have gained. The Village at Breck is a good example. They upgraded the building season before last. The assessment was over $55,000 per unit.

foreclosures are tempting, but most needs heavy repairs so be prepared.