Oops, clicked the wrong button and sent a post without my response to your questions.
1. Keep receipts for parts/materials, invoices for hired services, and yes charge for your labor if your jurisdiction allows it. We usually charge $20 per hour for our time, but in some situations (like really disgusting work) we have charged $30 per hour with no push back from the judge. We only have 14 days to return deposits or account for their withholding, so sometimes we must determine our costs before the repairs are complete. When tenants move-in we give them a list of customary charges for common damages, so they won't be blindsided. We give them the list again when we receive notice that they are moving. One of my favorite tools is HD Supply catalog because it gives prices on parts/materials for most anything needing replacement.
2. Yes she could file with the court, but why give her reason too? Whether a law suit has merit or is frivolous, it will still cost you time and money.
3. We have in our rental agreement: "ALTERATIONS: Tenant agrees not to alter the premises without prior written consent of Landlord. Landlord encourages Tenant to make the dwelling "their own home" and will allow a certain amount of decorating and modifications. However, all changes made by Tenant must be reversible and property must be restored to original condition at end of tenancy, unless other arrangement have been made with Landlord. Tenant agrees not to do painting, wallpapering or structural modifications to the premises. Tenant agrees not to make alterations, changes or additions to plumbing fixtures, light fixtures, heating units, or locks. Any alterations or decorations made by the Tenant become the property of the Landlord when Tenant vacates." That proactively covers it. If you didn't have an agreement in place that covers your situation, then be reasonable and in good faith negotiate a solution with the tenant.
4. Remain professional at all times. Only withhold the amount of security deposit that you are legally entitled to withhold. Follow proper procedure is compliance with landlord-tenant law. You may be inconvenienced, frustrated or angry by the tenants actions. Don't make it worse by your own actions. Remain calm and try to negotiate a win-win.
Let go of the 60-day notice concern. (Does your state allow you to require a 60-day notice? I thought it was 30-days in your state. Tenants do not waive their rights by signing contracts that are not in synch with the law.) When she gave you a 30-day verbal notice, you could have followed up by giving her some guidance to make the move-out process go more smoothly. Alas, you missed that opportunity this time. As you learn from this experience, you will become better at handling move-outs.
Here is our process, if you care to borrow it:
If a tenant informs us verbally of their intent to move, we remind them they must give us a written notice as per their rental agreement. We provide tenants with a Notice to Vacate form and move-out instructions at the time of move-in. By the time they decide to move, they have often misplaced the form, so we give them another one as soon as we hear wind that they are considering moving. They don't have to use our form, it just makes it easier for them and provides us with what we need.
When we receive their written Notice to Vacate, we mail them an acknowledgement letter that states the date of our receipt of the notice, the date we understand they will be out and what happens if they can't make it out by that date. We give them the move-out instructions again, which includes a list of common charges for damages. We remind them of the amount of their security deposit and what they must do to receive it back. Our forms and instructions reference applicable landlord-tenant law.
We keep an eye on the property to get an idea if they are preparing for their move and make a note if we observe a moving truck. If we do, are items being moved out or moved in? Believe it or not, we were evicting a tenant, saw the moving truck and thought YEAH! she really is moving! Until we noticed she was moving more items into the apartment, from a storage unit that had rent past due.
We ask the tenant to contact us to schedule a date and time for the move-out inspection. We prefer to do the move-out inspection with the tenant. We start by asking the tenant to show us any known damages. Then we ask the tenant anything in the unit is not working or needs repair. We point out any deficiencies that are beyond normal wear and tear and give the tenant a chance to take care of those.
We have had tenants clean an oven right then and there; we have also had tenants tell us to just deduct the cost of the oven cleaning from their security deposit. I never make promises to the tenant about how much of the security deposit they will get back. I do take photos of the deficiencies while we are doing the inspection, so they have a pretty good idea of what is coming. I almost always find something later that I overlooked during the move-out inspection, especially when cleaning - another reason I try to clean as soon as tenant moves out.
We have a Return of Possession form that both parties sign. In it, the tenant acknowledges they have moved out all of their belongings, have returned the keys and are ending their tenancy as of a specific date. It explains what we will do with any belongings we find left behind and references landlord-tenant law on the process for return of the security deposit.
We have a good track record for returning deposits because we nudge tenants to do what they need to do to get it back. In Washington State we have only 14 days to return the security deposit or provide a full explanation for the basis for which we retain any or all of the deposit. Its hard to meet that deadline when there are significant deficiencies to take care of, but we always do with at least one extra day to spare.
If the tenant does not want to do the move-out inspection with us, it is a red flag and usually points to damages that the tenant didn't want us to know about. If the tenancy ends because of a problem tenant, we rarely are able to get the tenant to do the move-out process in our customary way. That's okay, it just requires us to be extra diligent with our documentation.