Incorporating a washer-dryer hookup in the main house could be advantageous.This addition not only increases the convenience for potential renters but also adds value to the property itself.

You've probably heard of big Landlords losing property, but only because they were flagrantly violating Fair Housing, running a slum, or otherwise violating the law in an egregious manner.

Gas or electric would be a much better option, safety wise, from a house fire standpoint, CO danger, or danger to children or pets from the open flames. 

I just don't want to run into any problems with the lender when I am about to close on the house.

A "lake house" might be in a residential zoned area where a commercial use would be prohibited or at least require a variance (approval) to make an exception.

Stick it all in a rental, house-hack, index fund, or small business shot.

Then you own the LLC and can transfer the property into it.If you transfer the property into that LLC the way it is then technically you just gave your friend ownership of the house proportional to his ownership of the LLC.I'm not an attorney, so take that with a grain of salt.

Purchase price: $355,000 3 unit house hack with 2 separate buildings. 3 Bedroom/2 bath, 2 bedroom/2 bath, 1 bed/1 bath.

Unfortunately, it's now going to get more complicated:(There are two types of approaches PMCs use to bill for maintenance:1) In-house ServiceTechs on the payroll, so owners are billed for their time by the hour.While the labor charges above are useful, they don't cover the true costs a PMC incurs, like:- Payroll costs for FICA, Social Security, Medicare, etc. that typically add 25-40% to the hourly rate- Medical insurance costs for the worker- Payroll processing costs to handle all of the above- Liability insurance costs in case worker damages something or injures someone- Workman's Compensation insurance- Costs of vehicles and tools- and more...Typically the management contract will disclose the total hourly rate an owner will be charged.

I'm an investor and used to house hack.