Best of Luck To You
I have been doing foreclosures, construction cleanups, move ins, move outs, and a few vaction rentals for years.
First get all of you business items in order. Ficticous name, business registration, insurance and any licencing you may need.
There is a HUGE difference in doing rentals vs. foreclosures. Most rental are not trashed out. But foreclosures can be an undaunting challenge.
If you are going to JUST clean the foreclosure, (not clean out) be prepared to show all of your business insurance and licensing to the bank or the realtor as they WILL require it. Foreclosures can be tricky. You may think you have seen "everything" when you go to bid - but the hidden items can be the worst.
If you are going to repair foreclosures, think about partnering with someone who has a construction background if you personally do not have a background in this area.
I have run into crazy things from dead animals, rodent infestation, etc. to the electric, water and sewer that cannot be turned on because of unpaid bills. I have encountered broken pipes, no light fixtures (all had been taken). So make sure you know what kind of situation you will be working in.
Also, with a foreclosure, your payment can be slow. In my business area, right now, the banks do not want to spend money to clean them up. They want to turn them over to a realtor and put no money into them for repairs or clean up.
I wish you the best of luck in your business endeavor.