Now consider it may be more money but also consider the fact that if there is a claim you can count on your insurance to do what it was created to do which is to insure.

If you can get a reimbursement from the home warranty company, that's great, but I wouldn't count on it. 

Single dwelling with smaller floor plans are 650-700K in 2016Property under contract 620KCity of OrangeDirectly across local university Zoned: R16000 sq ft3bd/1ba - 1500 sq ft main dwelling$2700 rent for main dwellingmain dwelling needs 50k of rehab on its ownallowed up to a 640 sqft accessory unit with an attached garage that does not count against 640 sq ft.public access way available to accessory unit garage$1800 potential rent for accessory unitHave at it BP. 

First point, some banks will consider rental income from the other unit to count towards your DTI.

This method may require you to move into another rental yourself as many lenders need you to have a tenant renting your home for at least a year before they will count that income to offset your mortgage payment so you can qualify for a new mortgage. 

If so, you can count on your "economic vacancy" being a lot higher than what you are projecting due to non-paying tenants, plus higher and more frequent turnover costs.We would really need more information that what you provided. 

Even if you did find a property that had such great cash flow, lenders won't count rental income until you've been a landlord for at least two years, and even then they only count 75% of your income.

Can I really count on this not costing me money?

I am going on 12 years active duty now, have moved 7 times (not counting in-town moves or TDYs/deployments) so get used to this process!

@Ernesto Hernandez - the property you own and have a mortgage on that your mom lives in will count in your DTI.