I am about as good as any to answer your questions. Would you please let me know what state and city area this is in so I have some idea on jurisdiction? Please also tell me when the original work was done and planned / permitted?
Ok, I like your thinking as your being creative and could have stumbled over a real winner! There are lots of questions that need to be answered and a lot of research, due diligence and discovery work to make some determination.
There originally were steps taken to establish current condition and legal status in the county, this included zoning, planning, PUD application, tentative mapping, final mapping, entitlement, engineering, utility planning, access, easements, etc.
The problem with development is time dictates changes in technology, code changes, type of materials, sizing, set backs, off sets, loads, hydrology, soils and compaction ratio’s, storm water systems, etc. Chances are good that unless this property is just a few years old that some remediation and site work changes will have to occur.
Obviously new work has to be done to current code. It is likely that yes the last 50 lot’s could cost $18k +/- for site utilities including storm drain, sewer, water, electric, gas, cable and phone and the cost of fire hydrants, basic curb and streets in asphalt. This does not include anything for driveways, site utilities, site drainage, fire / life / safety, etc.
Just like a developer building townhouses as the lot size is similar you can bring in and stub everything on the lot at the street, the lot it’s self still needs to have everything set up in order to have a useable lot. If your state has contractors license law it’s unlikely you can do much of this work yourself.
Then we are assuming this property has 100 platted lot’s so we have to verify everything to verify legal lot’s. But what happens if this was done under a use permit, there are no legal individually deeded lots and the current structure does not meet current codes? Then what? This would mean the whole property would need to be redone to current code and would a mobile home park be highest and best use?
Even though there is old structure would it be better utilized as townhouses? Homes? Retail? Office? or Apartments? It may being sold cheap because current ownership knows it would cost to much to bring it to code to continue use as a mobile home park?
Depending on a homes size of lot site utilities with basic curb and street can run $20k to more than $50k per lot as an acre is 207’ x 207’ roughly and in order to provide utilities and streets to one acre lot’s requires a 207 foot run in length to get to the next lot!
It’s not advantage in bulk, it’s permit requirements in bulk as everything will have to be done at one time and 50 lot’s of streets and utilities could be a 4 to 6 month project depending on requirements, etc. Your probable talking a year to redo all site utilities as the existing system will probable have to be removed rather than vacated as your installing a lot of utilities in a small working area.
If these are individual lot’s and actually deeded your going to install site work (Lot work) separately and remember you could have both water and sewer tap fee’s involved! If adequate water rights don’t currently exist you may have to buy water rights (Water credits) in order to provide water for your community?
Your current infrastructure may be inadequate as water pipe sizing, electric load and meter / disconnect sizing may have changed, your sewer pipe may be under sized to support current structure and grossly undersized to add 50 new mobile homes?
If you have to redo the whole thing and there legally deeded lot’s this could cost you $3m to $5m just in structure!
If this is something you want to still do I could probable consult with you, you can PM me with your phone number and I will get back to you!