Quickest and easiest is if your assessor info is on line.

Online classified ads like Craigslist3.

I found the C-1 zoning regulations for the city, however I can not seem to find the height restrictions, does anyone know where online those might be?

I would build in a buffer for taxes to play it safe.

Feel free to PM me with your email address and I can send you the online re-stocking list and cleaning schedule that I use with my cleaner.  

If you are doing mailers or paying for clicks online, those 100 leads could get expensive.

Be very careful with this though, if you have shorter term financing like I do prepare for a down turn, I have no idea how much values fluctuate in your market, and if your note need to be renewed in a down market, you better have enough equity, or a pile of cash to bring in, I have seen many investors collapse because they harvested too much equity, I limit my portfolio to 40% LTV, im running about 35% on 21 properties right now, so i feel pretty safe, I was through the last crash and saw some guys i thought had it figured out crash and burn, just a word of warning. 

I understood your question to be about the various online auction sites such as Hudson & Marshall, Auction.com, etc.

Some of these will be no shows.If I have a tenant that is taking care of place I will likely show house while they are there.If they are slobs or place needs stuff like paint ot or repairs I will not advertise till I can take care of these so house will show well.I routinely use resident research.com for background checks but you Zillow offers online applications for $29 to the tenant.I turned this option on last vacancy and it worked really well.I told anyone that wanted to apply to go to Zillow and do so.

So, any problem with me taking online realtor classes for my pre-exam requirement!?