SFH or Trailer... PLEASE HELP!

[Curtis York Jr]

I have a dilema and felt like this was the best place to turn for advice please do not disappoint!

I am currently a teacher making around 30,000 a year on salary.  My credit score is fairly low but not terrible... Anyways I came across some real estate investors who are willing to seller finance a 2 bd 1.5 bathroom home in a not so quality neighborhood which is also about 45 minutes away from the town I work in.  The house goes for 66,000, but they offered me to place a down payment of 1,500 and Ill pay 650 a month in rent until I'm able to secure a proper mortgage through the bank once my credit score gets a little higher ( I have a 611, need a 620 to secure a loan).  They also offered to build a working relationship and mentorship with me in which I can become partner in their investment business and begin to see profits with them since I told them I was interested in investing.  However, while we were finalizing the deal I came across a 4 bed 3 bath trailer which is closer to my job literally 10 minutes away on more space and more land.  The trailer rents for 500 a month.  I am 23 years old with a family and I am trying to make sure I take the best deal because my decision doesn't only affect me but my family as well.  My biggest hesitation about the home is that the payments are fairly high and the risk of being locked into a long term mortgage that I may or may not be able to pay

Please help!