.... the main thing is not to let any 3rd party get involved. They will charge you 4 times the price of electricity.
...the best solution that I came up with is to pay your self for the installation of a plug at your space and ask the condo to bill you an extra 30$/month for "excessive" use of electricity.
At $30 per month even the more expensive third parties will be cheaper even without negotiation, and you'll still have to pay for a custom installation.
The options that appeared in my own research as the most practical were:
1. A personal installation that produces utility direct bill together with your unit electricity bill. That is preferred, but in large condominiums and ones that have multi-story parking or non-deeded parking this si frequently impossible. Further the individual installations can be much more expensive than are multi-unit installations. This solution works best with small units, ones that have parking spaces adjacent to the unit and ones that have prior unit direct billed electricity for other purposes, such as docks and outdoor spaces. Those situations apply less frequently in large urban buildings.
2. Convince the Condominium Association to offer charging as an amenity. That is rare, but it has happened especially when dealing direct with a developer. See the threads about the various Condominiums that have offered charging and the one famous one that gave Teslas to buyers. There are communities where this option can work, so if the Board members are enthusiastic and you can get a few owners to push it, this remains a possibility that is great if you can do it.
3. Third parties can be cheaper than other options. In my own case the installation cost with a third party was 1/3 the cost of doing it individually. The energy cost markup in my case, after negotiation, is 26% and my monthly service fee is $15. The payback for doing it individually would have been about 18 years, primarily due to very high installation costs and FPL sub metering installation. Based on my expected energy use I will average about $20 per month total use. In calculating the costs make sure to include actual expected use while at your own station. Many Tesla owners use Superchargers and other free charging sources for the majority of their power, and the home charging is primarily battery maintenance. By all means YMMV. These calculations are quite dependent on individual use patterns.
In my evaluation I was very lucky to have a friend and fellow Tesla owner who has living conditions quite similar to mine, but has two years of history. He shared that with me, resulting in a major reduction in my planned electrify consumption at home.
However, no question about it; if convenience and ease of administration are the biggest issues for you and the Association buys your logic, your solution may be more expensive but it is easier jam almost any other option, especially if you can just increase your unit monthly maintenance bill by $30. After all, time is money!
Finally, in my own case I was also trying to establish a permanent solution that will work for the Association dealing with both commercial and residential owners. Third parties can be pretty good in handling such issues. Until a few months ago there was little competition among multi-unit owner service EV charging. Now there is ChargePoint that has entered the fray, and EverCharge is more amenable to negotiation than they earlier may have been. There also are quite a few others now, most of whom operate in limited geographic areas. Our condominium precedent now will permit one of our major commercial tenants to install EV charging for their customers/employees, which they already do in most of their other facilities.