I get wanting lots of dry powder, just don't discount the rates or costs. 

Poured concrete is usually cheapest but there are other options such as dry-laid pavers, boardwalk decking, and asphalt.

You sold some securities in your Roth IRA account and withdrew not in excess of your life to date Roth IRA contributions and then contributed that into a Traditional IRA account?

Investors (Members) receive a 6-8% annual preferred return on their invested capital.Proceeds in excess of the preferred return is split 70/30 (LP/GP) based upon Members capital contributions.At the time of sale or capital event, all capital is first returned to contributing members, excess proceeds are split 70/30 (LP/GP). 

Inflation is going to force people to tighten their belts, the "free" COVID money from 2020/2021 is drying up, and mortgage rates are going to continue increasing in 2022 which starts making these high prices less affordable. 

Personally, i would take the credit line then not use it, and put all your excess funds on the mortgate.

I do think you can get people for excessive noise only if you don't tie it to kid age but noise complaints are always hard.

I have heard often that just because one lender has a certain opinion that is not necessarily the clear cut and dry answer altogether. 

I see a price point of 10k to be excessive and doesn't seem like a great sale to me. 

If so, you can use a HELOC finance your excess equity on your house out.