Usually when starting out, you are going to want to have liquid cash assets to a certain amount that depends on the market you are in. Down here in San Antonio, most first-time investors I run into typically will have $50,000 - $60,000 in cash to be able to comfortably afford putting a down payment and having funds set aside for renovation cost.
My question to you would be, how much funds do you currently have set aside for a real estate purchase? Yes, real estate investment properties are typically going to be way much cheaper than new construction builds, but you need to have proof of funds to show you are a serious buyer to sellers or realtors who can get you out to the right type of property flip you are looking for. Definitely aim at starting small, don't go after multifamily properties of over 2 doors.
For a fix and flip, be prepared to be cautious on which money lender you are going for. There are a ton of private money lenders who are licensed and qualified, and there are a ton of private money lenders who are scammers. For example, PMLs can agree to covering you at the closing table and advertise only 5% down or no money down, but they will have you sign on their stipulations in terms of amount of property ownership, or control over your property in the event something happens to them. Be very cautious.
Hard money financing gets you going fast, and are lenders who will design your loan amount for the purpose of your investment strategy. They will help you cover your closing cost and renovation expenses, so that your general contractors can get paid timely and have you ready to sell
Getting approved for only up to 100k sounds good, but may not be anywhere close to covering all the purchase price, your closing costs, plus renovation/rehab amounts for any project. How much are the duplexes are you seeing going for in your area of town? Does it necessarily have to be in Colorado? Have you considered buying and renting them out in El Paso?
If your desired duplex, for example, is offered to you at only $95,000, then a loan amount for only $100,000 just isn't going to cut it. If you have no money or proof of funds currently set aside for real estate, start saving now. You can do it!