I'm just lucky my guys called me before they threw the bucket and the bundle away.I have no expertise in this sort of thing and don't know how I should invest this unexpected windfall. 

Unit B has unexpected capex of $xx,xxx3.  

I have written before about the pitfalls of cost segregation, for example here: https://www.biggerpockets.com/forums/51/topics/831924-beware... and here: https://www.biggerpockets.com/forums/51/topics/1075919-five-...While cost segregation is an excellent and powerful strategy when used correctly and under the right circumstances, it is certainly not some master key that unlocks all doors all the time.

I don't know my buying power yet but I already have one house that's been rented out for a few years now. 

Equity plays can turn into better deals down the line with lower interest rates and a refi, with rent appreciation - where you can raise your rents because they may currently be lower than market, and with market appreciation - where the entire rental market moves upwards in rents.But you want to take a serious look at your challenges there... because there can be many - especially if you are a limited funds investor.Equity plays really only work well when you have enough income where you can cover the unexpected.  

Make sure to compare the costs and benefits of using your HELOC versus keeping it as a reserve for unexpected expenses.Market Conditions: Research the Dallas and suburb markets to understand demand, rental rates, and appreciation potential for both 4-plexes and duplexes.

All of my options are around the same dimensions so I've been looking at gallon amount as a more accurate gauge of how many people would fit.Largo LS 5 person tub:- $3,358.0: 200 gallons- H 29.5 in, W 61 in, D 71 in- Includes: Control Panel, Cover, Ozone water purification filter unit, LED Display, Power Cord, Pump, SensorsMalta 4 person- $3,589.00: 240 gallons- H 30 x W 57 x D 81- Includes: Cover, Filter Unit, [Ozone water sanitation system], Power Cord, Pump Ohana Spas dual facing lounger- $3,705.99: 200 gallons- H 29.5 x W 71 x D 61- Includes: Cover, Filter, Ozonator, Light LS100DX- $2999.00: 205 gallons- H 32 x W 62 x D 71- Includes: thermal locking cover, ozonator, multi-color underwater LED light, waterfall feature, two cup sliders, filter

The big issue for me being a foreigner was when I sold  REV CA keeps 25% of your proceeds until you file a final tax return.. and since I had a bunch of cash tied up in this that was un expected.

The project took too long, partly due to the power company taking 3 months to move service and poor communication with the county for permits.

It has 4 power, water and septic hook ups already on the property.