Luckily they didn't add up fast, but I didn't have them in the budget.

(probably included in the construction budget)Any realtor fees?

Also, as Levi said, it is hard to find here.Around Disney area, you need more budget to buy any kind of property.

What would be a good monthly budget?

@William Ellis , I think you are looking at this correctly.I think it is very smart to still budget for management because if you are going to be doing the management, you should be paid for that separately from how you are paid as the investor.If you are planning to hold for just a few years, you are probably correct your take home cashflow will be higher, but if you're planning to hold for the long term, that extra cash flow should probably be going into a future capex fund so you don't get blindsided when all those things need to be replaced at the same time.

Here's the equation:Income Producing Assets = Annual Expense Budget / ROIIf $100,000 per year will be enough for to afford to live the way I want to live without having to work, and my risk tolerance for my income producing assets says I can live with a 10% annual ROI, then the amount of Income Producing Assets I need is the following:Income Producing Assets = $100,000 / 10% = $1,000,000So now I have to come up with an Asset Accumulation Plan (AAP) to generate $1,000,000 so I can then convert the cash into income producing assets. 

For repair value, a good contracting team will be there to tell you accurate costs, and you can reasonably infer your budget based on purchase price and area market value. 

Those are the kinds of repairs that are tough to budget and could be huge costs.

Based on my numbers I have projected solid cash-on-cash returns (includes vacancy, property management, taxes, repair budget, etc.

Marketing costs are built into the structure of our business plan and are part of the budget for development but have not included closing cost nor did I include the realtor fees to sell these properties.