Cast iron plumbing is a pain in the you know what.

and read materials on bigger pockets- there is a ton of free materials, pod casts, etc all for free!

A house that old you also have older ungrounded wiring and cast iron plumbing drains to worry about.

I am a agent so i don't nor have i ever paid for them, if i have a investor come to me i would most likely cast for 100-150 depending how often i do them for him. 

I.e. cast yourself forward 5, 10 years.

I know that duplexes don't sell strictly on cap rates and that the 50% expense rule is not cast in stone but be careful.Good Luck.Bill

@Rick Fonseca my advice to you is make a habit of coming onto BP and reading articles, making posts and listening to pod casts.  

Install iTunes, download the pod casts and you can put them on a CD from there. 

I think the online stuff is good for some but not all. .I personally would not have the patience to listen to pod cast or webinars.

Condo's, Town Homes, Single Family Residences, or Multi Family Residences .2.What are the rental rates in your area- sometimes you will find that you can spend $100,000.00 in one area and get $800.00 a month in rent, but if you had bought a property 7 miles over you would spend the same amount of money but have received $1,100.00 instead.3.Negotiate a good price- If you can get an $80,000.00 property for $60,000.00 why not. 4.Plan out all of your expenses and put yourself in a good position.Bigger pockets have some great pod cast that you can listen to with hours of very useful information to help aid you in your investing career.