It's a tough nut to swallow, and we probably can't totally understand all the things running thru your head and the **** you will need to deal with.
I think I would put together an invoice for your time and material on the gate and put it into the mix of invoices to be signed and paid for. There is a cost to switching "contractors" and your dad needs to at least cover materials.
That said, I can see both sides of it. From his perspective, the gate and the office has been taking a long time. Frankly, he and most managers, could give two sh1ts about the minutia and myriad details for a project. And candidly, it probably doesn't really matter. It's not going to the moon. It just needs to be done.
From your perspective, it's worth doing things "right" but there needs to be a limit on it. Especially when in the bigger picture there is a greater value to the project being complete, not perfect. Many times, perfect is when it is done and usable. I do understand this quandary and it is easy to get caught in the paralysis.
I know you're probably frustrated to no end. Any of us would be, and that's understandable. That said, this could be a good thing long term. It's hard to look past all of this, but I think in two months and a year, it will be a better situation.
It does seem that the work and the hobbies are way too blended together. That may be fine if you were the boss, but as you're finding out, you're not.
In addition to getting your stuff separated and off the site, do you have a steady income stream after this all settles out? So you own any of the tower sites that you have full control over and will cash flow? Any way to add to your portfolio? Basically, if you're doing it for your dad, can you do it for yourself and turn yourself into the boss?
Final two cents, I would recommend scheduling time with your lawyer, accountant and a therapist. Time to get a plan for your business and someone to talk to in order to unpack all these issues and help you get aimed in the right direction. This is a lot to handle and you need people on your side to counsel and recommend.
Succession of family businesses certainly have the propensity to be sticky. It's ***** that you have to bare the brunt of it.
Regardless, we're pulling for you and keep your chin up and proceed forward. Do what is best for YOU (and your girlfriend and of course, your pets)

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