Things like mistakes to watch out for, things that I can do beforehand to speed up the process, taxes, fees, is it complicated, etc.?

I teach my clients to have all the expenses on auto withdrawal  ( mortgage payments, monthly assm, if needed: tax and insurance) and have the phone number of few handymen on speed dial.

Not only does this create a less fearful first contact environment for the seller, it also helps you qualify them before getting on the phone and best of all allows you to capture their phone number even if they don't leave a message.Although not directly related to finding the deals, I would add that in any highly competitive area speed and personal touch can make a huge difference.

I am in the process of buying a foreclosure  home in Florida, contract has been signed, home inspection has been performed and earnest money has been put down, my real estate agent has been trying to contact the seller to speed the process of paperwork for tomorrow's closing August 31, in the event that they don't answer by end of the day tomorrow, what is the next step to follow?

So I have been starting to expand my speed of investing in the upstate New York area and have found that I can severely lowballing properties that need some work and am getting a lot excepted.

Unfortunately, that's when we found out that speed on my end doesn't really gain you a lot of advantage with the VA. 

My initial plan is to get the extra cash I need for building more reserves and down payments by flipping/wholesaling, which I still want to do in order to speed things up.

you're a success in the making at least you took action and you learned a few things in the process you didn't back down your confidence should be at an all time high and feel good about yourself cause your next deal you get under contract it's a win win God speed

Trying to get back up to speed!

It is a bit easier to define and work on a niche in residential properties.I personally wouldn't focus on the speed of acquiring the money,  and place more of the focus on the consistancy of earning money.