Simultaneous closings are a "hassle" no matter how you pay for the property. If you are buying an REO (Bank Foreclosure) or a Short Sale, most banks in these circumstances require that you either hold the home for 30 days or disclose what you are doing. Due to the wording on the seller or short sale bank's documents, title companies cannot insure such a deal. If you are buying directly from a seller with equity, you might be able to do this.
You best bet, shop for a title company that will consider doing a simultaneous closing and them send them all your deals, even those where you cannot (due to contractual reasons) do such a closing. Most of the title companies I know, in California, will not longer do simultaneous closings, no matter what, due to the liability. However, you might find an investor friendly company that does. Shop around, ask questions at Real Estate Investor blogs, meetings, etc. and you might find the solution to your dilema. Dare to Dream.
Shel-lee Davis, CDPE
Your Real Estate Consultant for Life
RE/MAX Palos Verdes Realty