So I market the property as a lease option where, for a fee, a tenant/buyer can lock in a price right now that they can purchase the property for within the option timeframe.  

You can meet them there to evict literally and change the locks.

@Jingwen Dunford LPs are generally not involved in the contract or negotiation phase of locking up the deal.

The cheapest path appears to be to remove the vault door and prevent liability of someone getting locked inside and use the inside as a store-room.

If I quote a rate you are going to hold me accountable for it even when I tell you, verbally and in writing that it is subject to change till the time of lock.

I was a little nervous because I didn't know what to expect as far as bookings since there was not one other 4 BR home being rented in the market (that I could find).We luckily realized that the floor plan/layout of the house would allow us to configure it into 2 lock-off 2 BR/1 BA apartments as well as one complete 4 BR/2 BA house so we felt better about being able to compete with the other STRs in the market.To our surprise (and delight) it turns our the house has been rented most often as the 4 BR/2 BA configuration over the smaller apartments.

We’re going to change the locks and check all the windows to make sure they’re working/locking properly.

Would you guys risk locking up your money like this?

I was recently working with my investor to lock down a property in West Philly and his lender changed the rates since the "As-Is" appraisal came in 15k lower than purchase price of the property (the appraiser ignored the condition of the property and comparing it to properties that were damn near shells, but I digress.) 

So the longer leases really just end up locking the landlord in.