Hello, Congrats on your choosing to take your first steps in becoming a REI. True, some markets like San Diego are expensive. Especially, if you decide to buy in San Diego neighborhoods near high demand or popular areas such as beaches, entertainment, tourism, etc. Highly recommend driving around or checking out deals on Zillow, Redfin, Trulia , Craigslist, rentometer and other apps or sites to find deals from For sale by owners ( FSBO: some are motivated, some Distress), Government ( FHA, HUD, VA, etc.), Banks (Real estate owned: REO, etc.). Read and post value added questions or information to BP , Reddit and other real estate blogs and forums. At your local library, kindle, etc. read as many or all real estate investing books then take or record notes. To not lose money, have a negative cash flow, be underwater in your mortgage (owe more on your mortgage than the property market value ) analyze at least 10 properties cash on cash, ROI (return on investment), Internal rate of return (IRR), capitalization rate (cap rate), rent to value, debt coverage (DCR), Gross rent multiplier (GRM) are some ratios used in property analysis of SFR or MF rental investments. You will need to gather assumptions or facts on property management fees (10% typical average), vacancy rate, down payment or skin in the game (typically 20% for conventional bank mortgages or 25% hard money lenders), purchase costs ( could be more or less than asking price), rehab costs/expenses( estimated costs of repairs in your area on common repairs/ fix up costs to make Rental habitability, security, safety within or above state and local landlord/ tenant laws/codes). Closing or purchase cost for your area ( everything from appraisal, origination fees, real estate broker/agent fees [3% to 6%], title search and insurance, and more). There are many ways to acquire financing or funds/ capital etc. you need: hard money lenders, traditional banks ( investors pay more in interest than owner occupant status home buyers), partners, family and friends, retirement funds ( maybe Roth), private lenders, mortgage brokers, crowd funding, seller financing, savings, rents/ dividends/ interest and other income, etc. I believe in paying yourself first. Every paycheck (earned income) or other income- take minimum of 10% of the top - automatically if you prefer towards savings or money market account or Bank CD, mutual fund, index fund, ETF , Government treasury bond etc. Think about property taxes ( after year one of purchase: prepare for California supplemental property tax) . San Diego and California ( maybe 1.5% of purchase price into your calculations). Of course you will need the right hazard insurance added to your calculations ( hopefully no flood or earthquake; etc.). I used BP property analyzer and a free deal check app to do my preliminary ball park on whether a property will have a positive cash flow. Do not forget to use the above and other sources like tenants, property managers, real estate agents, etc. to get an idea of what maximum rental income the rental will bring in month to month. You tube has a lot of videos on real estate investing and property analysts: google or go to you tube; then type in rental property analysis or single family rental property analyzer or analysis. Good luck!