Need info on self directed IRA's for park

This is my first post on this site; my husband and I have been considering a park as a source of retirement income. Right now I am asking for advice from people with experience using a self directed IRA’s for this type of purchase. Our personal info is that we are both going to be 65 this year. My husband receives only social security and is physically unable to do much due to back surgeries and pain. I am working full time at about 50,000 income. I must also say I am paying off a chapter 13 bankruptcy, have four more years to go. Our only source for investment is for me to retire and use my 45000-50000 403 as a self directed IRA for down payment. I could continue to work at another job if necessary as long as health allows. I have two main issues to ask right now

  1. how does the self directed IRA work for something like this??

  2. is it possible for a park to replace this amont of income? When we are unable to do much physical labor, is it a practical idea?

thanks for any reply